diff --git a/docs/specification/2026-07-28/schema.mdx b/docs/specification/2026-07-28/schema.mdx
index 706453adc..da8c4bc7a 100644
--- a/docs/specification/2026-07-28/schema.mdx
+++ b/docs/specification/2026-07-28/schema.mdx
@@ -1506,14 +1506,17 @@ different cache).</li> </ul> </div><aside class="tsd-sources"> <p>Inherited from
 
 ### `Tool`
 
-<div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Tool</span> <span class="tsd-signature-symbol">&#x7B;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-icons">icons</a><span class="tsd-signature-symbol">?:</span> <a href="#icon" class="tsd-signature-type tsd-kind-interface">Icon</a><span class="tsd-signature-symbol">&#x5B;]</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-name">name</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-title">title</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-description">description</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-inputschema">inputSchema</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-kind-property">type</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">&quot;object&quot;</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-outputschema">outputSchema</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-annotations">annotations</a><span class="tsd-signature-symbol">?:</span> <a href="#toolannotations" class="tsd-signature-type tsd-kind-interface">ToolAnnotations</a><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-&#x5F;meta">&#x5F;meta</a><span class="tsd-signature-symbol">?:</span> <a href="#metaobject" class="tsd-signature-type tsd-kind-type-alias">MetaObject</a><span class="tsd-signature-symbol">;</span><br/><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Definition for a tool the client can call.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With default 2020-12 input schema<a href="#tool-example-with-default-2020-12-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-default-2020-12-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With explicit draft-07 input schema<a href="#tool-example-with-explicit-draft-07-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-explicit-draft-07-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;&#x24;schema&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;http://json-schema.org/draft-07/schema#&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With no parameters<a href="#tool-example-with-no-parameters" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-no-parameters"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;current&#x5F;time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Returns the current server time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;additionalProperties&quot;</span><span class="hl-0">: </span><span class="hl-5">false</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With output schema for structured content<a href="#tool-example-with-output-schema-for-structured-content" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-output-schema-for-structured-content"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;weather&#x5F;data&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather Data Retriever&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Get current weather data for a location&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;location&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;City name or zip code&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;location&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  },</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;outputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;temperature&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Temperature in celsius&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;conditions&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather conditions description&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;humidity&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Humidity percentage&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;temperature&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;conditions&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;humidity&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-icons" data-typedoc-h="3"><span>icons?: Icon&#x5B;]</span><a href="#tool-icons" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional set of sized icons that the client can display in a user interface.</p> <p>Clients that support rendering icons MUST support at least the following MIME types:</p> <ul> <li><code>image/png</code> - PNG images (safe, universal compatibility)</li> <li><code>image/jpeg</code> (and <code>image/jpg</code>) - JPEG images (safe, universal compatibility)</li> </ul> <p>Clients that support rendering icons SHOULD also support:</p> <ul> <li><code>image/svg+xml</code> - SVG images (scalable but requires security precautions)</li> <li><code>image/webp</code> - WebP images (modern, efficient format)</li> </ul> </div><aside class="tsd-sources"> <p>Inherited from Icons.icons</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-name" data-typedoc-h="3"><span>name: string</span><a href="#tool-name" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for programmatic or logical use, but used as a display name in past specs or fallback (if title isn't present).</p> </div><aside class="tsd-sources"> <p>Inherited from BaseMetadata.name</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-title" data-typedoc-h="3"><span>title?: string</span><a href="#tool-title" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for UI and end-user contexts — optimized to be human-readable and easily understood,
+<div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Tool</span> <span class="tsd-signature-symbol">&#x7B;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-icons">icons</a><span class="tsd-signature-symbol">?:</span> <a href="#icon" class="tsd-signature-type tsd-kind-interface">Icon</a><span class="tsd-signature-symbol">&#x5B;]</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-name">name</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-title">title</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-description">description</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-inputschema">inputSchema</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-kind-property">type</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">&quot;object&quot;</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-outputschema">outputSchema</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-annotations">annotations</a><span class="tsd-signature-symbol">?:</span> <a href="#toolannotations" class="tsd-signature-type tsd-kind-interface">ToolAnnotations</a><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-&#x5F;meta">&#x5F;meta</a><span class="tsd-signature-symbol">?:</span> <a href="#metaobject" class="tsd-signature-type tsd-kind-type-alias">MetaObject</a><span class="tsd-signature-symbol">;</span><br/><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Definition for a tool the client can call.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With default 2020-12 input schema<a href="#tool-example-with-default-2020-12-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-default-2020-12-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With explicit draft-07 input schema<a href="#tool-example-with-explicit-draft-07-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-explicit-draft-07-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;&#x24;schema&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;http://json-schema.org/draft-07/schema#&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With no parameters<a href="#tool-example-with-no-parameters" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-no-parameters"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;current&#x5F;time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Returns the current server time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;additionalProperties&quot;</span><span class="hl-0">: </span><span class="hl-5">false</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With a composition input schema<a href="#tool-example-with-a-composition-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-a-composition-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;find&#x5F;resource&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Resource Finder&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Find a resource by ID or name&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;id&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Resource ID&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Resource name&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;oneOf&quot;</span><span class="hl-0">: &#x5B;&#x7B; </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;id&quot;</span><span class="hl-0">] }, &#x7B; </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;name&quot;</span><span class="hl-0">] }]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With output schema for structured content<a href="#tool-example-with-output-schema-for-structured-content" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-output-schema-for-structured-content"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;weather&#x5F;data&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather Data Retriever&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Get current weather data for a location&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;location&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;City name or zip code&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;location&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  },</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;outputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;temperature&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Temperature in celsius&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;conditions&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather conditions description&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;humidity&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Humidity percentage&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;temperature&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;conditions&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;humidity&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With an array output schema<a href="#tool-example-with-an-array-output-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-an-array-output-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;list&#x5F;users&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User List&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Returns a list of all users&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;}</span><br/><span class="hl-0">  },</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;outputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;array&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;items&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;id&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User ID&quot;</span><br/><span class="hl-0">        },</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User name&quot;</span><br/><span class="hl-0">        },</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;email&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User email&quot;</span><br/><span class="hl-0">        }</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;id&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;name&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;email&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">    }</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-icons" data-typedoc-h="3"><span>icons?: Icon&#x5B;]</span><a href="#tool-icons" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional set of sized icons that the client can display in a user interface.</p> <p>Clients that support rendering icons MUST support at least the following MIME types:</p> <ul> <li><code>image/png</code> - PNG images (safe, universal compatibility)</li> <li><code>image/jpeg</code> (and <code>image/jpg</code>) - JPEG images (safe, universal compatibility)</li> </ul> <p>Clients that support rendering icons SHOULD also support:</p> <ul> <li><code>image/svg+xml</code> - SVG images (scalable but requires security precautions)</li> <li><code>image/webp</code> - WebP images (modern, efficient format)</li> </ul> </div><aside class="tsd-sources"> <p>Inherited from Icons.icons</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-name" data-typedoc-h="3"><span>name: string</span><a href="#tool-name" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for programmatic or logical use, but used as a display name in past specs or fallback (if title isn't present).</p> </div><aside class="tsd-sources"> <p>Inherited from BaseMetadata.name</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-title" data-typedoc-h="3"><span>title?: string</span><a href="#tool-title" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for UI and end-user contexts — optimized to be human-readable and easily understood,
 even by those unfamiliar with domain-specific terminology.</p> <p>If not provided, the name should be used for display (except for <a href="#" class="tsd-kind-interface">Tool</a>,
 where <code>annotations.title</code> should be given precedence over using <code>name</code>,
 if present).</p> </div><aside class="tsd-sources"> <p>Inherited from BaseMetadata.title</p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="tool-description" data-typedoc-h="3"><span>description?: string</span><a href="#tool-description" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>A human-readable description of the tool.</p> <p>This can be used by clients to improve the LLM's understanding of available tools. It can be thought of like a &quot;hint&quot; to the model.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="tool-inputschema" data-typedoc-h="3"><span>inputSchema: &#x7B; &#x24;schema?: string; type: &quot;object&quot;; &#x5B;key: string]: unknown }</span><a href="#tool-inputschema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>A JSON Schema object defining the expected parameters for the tool.</p> <p>Tool arguments are always JSON objects, so <code>type: &quot;object&quot;</code> is required at the root.
 Beyond that, any JSON Schema 2020-12 keyword may appear alongside <code>type</code> — including
 composition keywords (<code>oneOf</code>, <code>anyOf</code>, <code>allOf</code>, <code>not</code>), conditional keywords
 (<code>if</code>/<code>then</code>/<code>else</code>), reference keywords (<code>&#x24;ref</code>, <code>&#x24;defs</code>, <code>&#x24;anchor</code>), and any other
-standard validation or annotation keywords.</p> <p>Property schemas may carry an <code>x-mcp-header</code> annotation to mirror the
+standard validation or annotation keywords.</p> <p>When using composition keywords, declare <code>properties</code> at the schema root and keep the
+branches to presence assertions such as <code>required</code>. A subschema that fails on a type
+error is indistinguishable from one that does not apply, so type constraints placed
+inside <code>oneOf</code> branches are not enforced for whichever branch does not match.</p> <p>Property schemas may carry an <code>x-mcp-header</code> annotation to mirror the
 argument value into an HTTP header on the Streamable HTTP transport. See
 the Streamable HTTP transport specification for the validity and
 extraction rules.</p> <p>Defaults to JSON Schema 2020-12 when no explicit <code>&#x24;schema</code> is provided.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="tool-outputschema" data-typedoc-h="3"><span>outputSchema?: &#x7B; &#x24;schema?: string; &#x5B;key: string]: unknown }</span><a href="#tool-outputschema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>An optional JSON Schema object defining the structure of the tool's output returned in
diff --git a/docs/specification/draft/schema.mdx b/docs/specification/draft/schema.mdx
index 159c7be5e..fb6b8b7f4 100644
--- a/docs/specification/draft/schema.mdx
+++ b/docs/specification/draft/schema.mdx
@@ -1506,14 +1506,17 @@ different cache).</li> </ul> </div><aside class="tsd-sources"> <p>Inherited from
 
 ### `Tool`
 
-<div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Tool</span> <span class="tsd-signature-symbol">&#x7B;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-icons">icons</a><span class="tsd-signature-symbol">?:</span> <a href="#icon" class="tsd-signature-type tsd-kind-interface">Icon</a><span class="tsd-signature-symbol">&#x5B;]</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-name">name</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-title">title</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-description">description</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-inputschema">inputSchema</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-kind-property">type</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">&quot;object&quot;</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-outputschema">outputSchema</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-annotations">annotations</a><span class="tsd-signature-symbol">?:</span> <a href="#toolannotations" class="tsd-signature-type tsd-kind-interface">ToolAnnotations</a><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-&#x5F;meta">&#x5F;meta</a><span class="tsd-signature-symbol">?:</span> <a href="#metaobject" class="tsd-signature-type tsd-kind-type-alias">MetaObject</a><span class="tsd-signature-symbol">;</span><br/><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Definition for a tool the client can call.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With default 2020-12 input schema<a href="#tool-example-with-default-2020-12-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-default-2020-12-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With explicit draft-07 input schema<a href="#tool-example-with-explicit-draft-07-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-explicit-draft-07-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;&#x24;schema&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;http://json-schema.org/draft-07/schema#&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With no parameters<a href="#tool-example-with-no-parameters" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-no-parameters"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;current&#x5F;time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Returns the current server time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;additionalProperties&quot;</span><span class="hl-0">: </span><span class="hl-5">false</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With output schema for structured content<a href="#tool-example-with-output-schema-for-structured-content" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-output-schema-for-structured-content"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;weather&#x5F;data&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather Data Retriever&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Get current weather data for a location&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;location&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;City name or zip code&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;location&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  },</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;outputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;temperature&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Temperature in celsius&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;conditions&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather conditions description&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;humidity&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Humidity percentage&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;temperature&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;conditions&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;humidity&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-icons" data-typedoc-h="3"><span>icons?: Icon&#x5B;]</span><a href="#tool-icons" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional set of sized icons that the client can display in a user interface.</p> <p>Clients that support rendering icons MUST support at least the following MIME types:</p> <ul> <li><code>image/png</code> - PNG images (safe, universal compatibility)</li> <li><code>image/jpeg</code> (and <code>image/jpg</code>) - JPEG images (safe, universal compatibility)</li> </ul> <p>Clients that support rendering icons SHOULD also support:</p> <ul> <li><code>image/svg+xml</code> - SVG images (scalable but requires security precautions)</li> <li><code>image/webp</code> - WebP images (modern, efficient format)</li> </ul> </div><aside class="tsd-sources"> <p>Inherited from Icons.icons</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-name" data-typedoc-h="3"><span>name: string</span><a href="#tool-name" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for programmatic or logical use, but used as a display name in past specs or fallback (if title isn't present).</p> </div><aside class="tsd-sources"> <p>Inherited from BaseMetadata.name</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-title" data-typedoc-h="3"><span>title?: string</span><a href="#tool-title" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for UI and end-user contexts — optimized to be human-readable and easily understood,
+<div class="tsd-signature"><span class="tsd-signature-keyword">interface</span> <span class="tsd-kind-interface">Tool</span> <span class="tsd-signature-symbol">&#x7B;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-icons">icons</a><span class="tsd-signature-symbol">?:</span> <a href="#icon" class="tsd-signature-type tsd-kind-interface">Icon</a><span class="tsd-signature-symbol">&#x5B;]</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-name">name</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-title">title</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-description">description</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-inputschema">inputSchema</a><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-kind-property">type</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">&quot;object&quot;</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-outputschema">outputSchema</a><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-symbol">&#x7B;</span> <span class="tsd-kind-property">&#x24;schema</span><span class="tsd-signature-symbol">?:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">;</span> <span class="tsd-signature-symbol">&#x5B;</span><span class="tsd-kind-index-signature">key</span><span class="tsd-signature-symbol">:</span> <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol">]:</span> <span class="tsd-signature-type">unknown</span> <span class="tsd-signature-symbol">}</span><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-annotations">annotations</a><span class="tsd-signature-symbol">?:</span> <a href="#toolannotations" class="tsd-signature-type tsd-kind-interface">ToolAnnotations</a><span class="tsd-signature-symbol">;</span><br/>&nbsp;&nbsp;<a class="tsd-kind-property" href="#tool-&#x5F;meta">&#x5F;meta</a><span class="tsd-signature-symbol">?:</span> <a href="#metaobject" class="tsd-signature-type tsd-kind-type-alias">MetaObject</a><span class="tsd-signature-symbol">;</span><br/><span class="tsd-signature-symbol">}</span></div> <div class="tsd-comment tsd-typography"><p>Definition for a tool the client can call.</p> </div> <div class="tsd-comment tsd-typography"> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With default 2020-12 input schema<a href="#tool-example-with-default-2020-12-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-default-2020-12-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With explicit draft-07 input schema<a href="#tool-example-with-explicit-draft-07-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-explicit-draft-07-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;calculate&#x5F;sum&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Add two numbers&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;&#x24;schema&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;http://json-schema.org/draft-07/schema#&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;a&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;b&quot;</span><span class="hl-0">: &#x7B; </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0"> }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;a&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;b&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With no parameters<a href="#tool-example-with-no-parameters" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-no-parameters"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;current&#x5F;time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Returns the current server time&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;additionalProperties&quot;</span><span class="hl-0">: </span><span class="hl-5">false</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With a composition input schema<a href="#tool-example-with-a-composition-input-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-a-composition-input-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;find&#x5F;resource&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Resource Finder&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Find a resource by ID or name&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;id&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Resource ID&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Resource name&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;oneOf&quot;</span><span class="hl-0">: &#x5B;&#x7B; </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;id&quot;</span><span class="hl-0">] }, &#x7B; </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;name&quot;</span><span class="hl-0">] }]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With output schema for structured content<a href="#tool-example-with-output-schema-for-structured-content" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-output-schema-for-structured-content"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;get&#x5F;weather&#x5F;data&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather Data Retriever&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Get current weather data for a location&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;location&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;City name or zip code&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;location&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  },</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;outputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;temperature&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Temperature in celsius&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;conditions&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Weather conditions description&quot;</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;humidity&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;number&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Humidity percentage&quot;</span><br/><span class="hl-0">      }</span><br/><span class="hl-0">    },</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;temperature&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;conditions&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;humidity&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details> <details class="tsd-tag-example"> <summary class="tsd-anchor-link">Example: With an array output schema<a href="#tool-example-with-an-array-output-schema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></summary><pre id="tool-example-with-an-array-output-schema"><code class="json"><span class="hl-0">&#x7B;</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;list&#x5F;users&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;title&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User List&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;Returns a list of all users&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;inputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;}</span><br/><span class="hl-0">  },</span><br/><span class="hl-0">  </span><span class="hl-1">&quot;outputSchema&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;array&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">    </span><span class="hl-1">&quot;items&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;object&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;properties&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;id&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User ID&quot;</span><br/><span class="hl-0">        },</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;name&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User name&quot;</span><br/><span class="hl-0">        },</span><br/><span class="hl-0">        </span><span class="hl-1">&quot;email&quot;</span><span class="hl-0">: &#x7B;</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;type&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;string&quot;</span><span class="hl-0">,</span><br/><span class="hl-0">          </span><span class="hl-1">&quot;description&quot;</span><span class="hl-0">: </span><span class="hl-2">&quot;User email&quot;</span><br/><span class="hl-0">        }</span><br/><span class="hl-0">      },</span><br/><span class="hl-0">      </span><span class="hl-1">&quot;required&quot;</span><span class="hl-0">: &#x5B;</span><span class="hl-2">&quot;id&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;name&quot;</span><span class="hl-0">, </span><span class="hl-2">&quot;email&quot;</span><span class="hl-0">]</span><br/><span class="hl-0">    }</span><br/><span class="hl-0">  }</span><br/><span class="hl-0">}</span> </code><button type="button">Copy</button></pre> </details></div> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-icons" data-typedoc-h="3"><span>icons?: Icon&#x5B;]</span><a href="#tool-icons" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Optional set of sized icons that the client can display in a user interface.</p> <p>Clients that support rendering icons MUST support at least the following MIME types:</p> <ul> <li><code>image/png</code> - PNG images (safe, universal compatibility)</li> <li><code>image/jpeg</code> (and <code>image/jpg</code>) - JPEG images (safe, universal compatibility)</li> </ul> <p>Clients that support rendering icons SHOULD also support:</p> <ul> <li><code>image/svg+xml</code> - SVG images (scalable but requires security precautions)</li> <li><code>image/webp</code> - WebP images (modern, efficient format)</li> </ul> </div><aside class="tsd-sources"> <p>Inherited from Icons.icons</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-name" data-typedoc-h="3"><span>name: string</span><a href="#tool-name" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for programmatic or logical use, but used as a display name in past specs or fallback (if title isn't present).</p> </div><aside class="tsd-sources"> <p>Inherited from BaseMetadata.name</p></aside></section> <section class="tsd-panel tsd-member tsd-is-inherited"> <div class="tsd-anchor-link" id="tool-title" data-typedoc-h="3"><span>title?: string</span><a href="#tool-title" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>Intended for UI and end-user contexts — optimized to be human-readable and easily understood,
 even by those unfamiliar with domain-specific terminology.</p> <p>If not provided, the name should be used for display (except for <a href="#" class="tsd-kind-interface">Tool</a>,
 where <code>annotations.title</code> should be given precedence over using <code>name</code>,
 if present).</p> </div><aside class="tsd-sources"> <p>Inherited from BaseMetadata.title</p></aside></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="tool-description" data-typedoc-h="3"><span>description?: string</span><a href="#tool-description" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>A human-readable description of the tool.</p> <p>This can be used by clients to improve the LLM's understanding of available tools. It can be thought of like a &quot;hint&quot; to the model.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="tool-inputschema" data-typedoc-h="3"><span>inputSchema: &#x7B; &#x24;schema?: string; type: &quot;object&quot;; &#x5B;key: string]: unknown }</span><a href="#tool-inputschema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>A JSON Schema object defining the expected parameters for the tool.</p> <p>Tool arguments are always JSON objects, so <code>type: &quot;object&quot;</code> is required at the root.
 Beyond that, any JSON Schema 2020-12 keyword may appear alongside <code>type</code> — including
 composition keywords (<code>oneOf</code>, <code>anyOf</code>, <code>allOf</code>, <code>not</code>), conditional keywords
 (<code>if</code>/<code>then</code>/<code>else</code>), reference keywords (<code>&#x24;ref</code>, <code>&#x24;defs</code>, <code>&#x24;anchor</code>), and any other
-standard validation or annotation keywords.</p> <p>Property schemas may carry an <code>x-mcp-header</code> annotation to mirror the
+standard validation or annotation keywords.</p> <p>When using composition keywords, declare <code>properties</code> at the schema root and keep the
+branches to presence assertions such as <code>required</code>. A subschema that fails on a type
+error is indistinguishable from one that does not apply, so type constraints placed
+inside <code>oneOf</code> branches are not enforced for whichever branch does not match.</p> <p>Property schemas may carry an <code>x-mcp-header</code> annotation to mirror the
 argument value into an HTTP header on the Streamable HTTP transport. See
 the Streamable HTTP transport specification for the validity and
 extraction rules.</p> <p>Defaults to JSON Schema 2020-12 when no explicit <code>&#x24;schema</code> is provided.</p> </div></section> <section class="tsd-panel tsd-member"> <div class="tsd-anchor-link" id="tool-outputschema" data-typedoc-h="3"><span>outputSchema?: &#x7B; &#x24;schema?: string; &#x5B;key: string]: unknown }</span><a href="#tool-outputschema" aria-label="Permalink" class="tsd-anchor-icon"><svg viewBox="0 0 24 24" aria-hidden="true"><use href="assets/icons.svg#icon-anchor"/></svg></a></div> <div class="tsd-comment tsd-typography"><p>An optional JSON Schema object defining the structure of the tool's output returned in
diff --git a/schema/2026-07-28/examples/Tool/tool-with-composition-input-schema.json b/schema/2026-07-28/examples/Tool/tool-with-composition-input-schema.json
index 7c7253af9..aaaf501f4 100644
--- a/schema/2026-07-28/examples/Tool/tool-with-composition-input-schema.json
+++ b/schema/2026-07-28/examples/Tool/tool-with-composition-input-schema.json
@@ -4,25 +4,16 @@
   "description": "Find a resource by ID or name",
   "inputSchema": {
     "type": "object",
-    "oneOf": [
-      {
-        "properties": {
-          "id": {
-            "type": "string",
-            "description": "Resource ID"
-          }
-        },
-        "required": ["id"]
+    "properties": {
+      "id": {
+        "type": "string",
+        "description": "Resource ID"
       },
-      {
-        "properties": {
-          "name": {
-            "type": "string",
-            "description": "Resource name"
-          }
-        },
-        "required": ["name"]
+      "name": {
+        "type": "string",
+        "description": "Resource name"
       }
-    ]
+    },
+    "oneOf": [{ "required": ["id"] }, { "required": ["name"] }]
   }
 }
diff --git a/schema/2026-07-28/schema.json b/schema/2026-07-28/schema.json
index 213c58f6d..0b9ba317f 100644
--- a/schema/2026-07-28/schema.json
+++ b/schema/2026-07-28/schema.json
@@ -3638,7 +3638,7 @@
                 },
                 "inputSchema": {
                     "additionalProperties": {},
-                    "description": "A JSON Schema object defining the expected parameters for the tool.\n\nTool arguments are always JSON objects, so `type: \"object\"` is required at the root.\nBeyond that, any JSON Schema 2020-12 keyword may appear alongside `type` — including\ncomposition keywords (`oneOf`, `anyOf`, `allOf`, `not`), conditional keywords\n(`if`/`then`/`else`), reference keywords (`$ref`, `$defs`, `$anchor`), and any other\nstandard validation or annotation keywords.\n\nProperty schemas may carry an `x-mcp-header` annotation to mirror the\nargument value into an HTTP header on the Streamable HTTP transport. See\nthe Streamable HTTP transport specification for the validity and\nextraction rules.\n\nDefaults to JSON Schema 2020-12 when no explicit `$schema` is provided.",
+                    "description": "A JSON Schema object defining the expected parameters for the tool.\n\nTool arguments are always JSON objects, so `type: \"object\"` is required at the root.\nBeyond that, any JSON Schema 2020-12 keyword may appear alongside `type` — including\ncomposition keywords (`oneOf`, `anyOf`, `allOf`, `not`), conditional keywords\n(`if`/`then`/`else`), reference keywords (`$ref`, `$defs`, `$anchor`), and any other\nstandard validation or annotation keywords.\n\nWhen using composition keywords, declare `properties` at the schema root and keep the\nbranches to presence assertions such as `required`. A subschema that fails on a type\nerror is indistinguishable from one that does not apply, so type constraints placed\ninside `oneOf` branches are not enforced for whichever branch does not match.\n\nProperty schemas may carry an `x-mcp-header` annotation to mirror the\nargument value into an HTTP header on the Streamable HTTP transport. See\nthe Streamable HTTP transport specification for the validity and\nextraction rules.\n\nDefaults to JSON Schema 2020-12 when no explicit `$schema` is provided.",
                     "properties": {
                         "$schema": {
                             "type": "string"
diff --git a/schema/2026-07-28/schema.ts b/schema/2026-07-28/schema.ts
index 9b55feeb4..0abde3c55 100644
--- a/schema/2026-07-28/schema.ts
+++ b/schema/2026-07-28/schema.ts
@@ -1965,9 +1965,15 @@ export interface ToolAnnotations {
  * @example With no parameters
  * {@includeCode ./examples/Tool/with-no-parameters.json}
  *
+ * @example With a composition input schema
+ * {@includeCode ./examples/Tool/tool-with-composition-input-schema.json}
+ *
  * @example With output schema for structured content
  * {@includeCode ./examples/Tool/with-output-schema-for-structured-content.json}
  *
+ * @example With an array output schema
+ * {@includeCode ./examples/Tool/tool-with-array-output-schema.json}
+ *
  * @category `tools/list`
  */
 export interface Tool extends BaseMetadata, Icons {
@@ -1987,6 +1993,11 @@ export interface Tool extends BaseMetadata, Icons {
    * (`if`/`then`/`else`), reference keywords (`$ref`, `$defs`, `$anchor`), and any other
    * standard validation or annotation keywords.
    *
+   * When using composition keywords, declare `properties` at the schema root and keep the
+   * branches to presence assertions such as `required`. A subschema that fails on a type
+   * error is indistinguishable from one that does not apply, so type constraints placed
+   * inside `oneOf` branches are not enforced for whichever branch does not match.
+   *
    * Property schemas may carry an `x-mcp-header` annotation to mirror the
    * argument value into an HTTP header on the Streamable HTTP transport. See
    * the Streamable HTTP transport specification for the validity and
diff --git a/schema/draft/examples/Tool/tool-with-composition-input-schema.json b/schema/draft/examples/Tool/tool-with-composition-input-schema.json
index 7c7253af9..aaaf501f4 100644
--- a/schema/draft/examples/Tool/tool-with-composition-input-schema.json
+++ b/schema/draft/examples/Tool/tool-with-composition-input-schema.json
@@ -4,25 +4,16 @@
   "description": "Find a resource by ID or name",
   "inputSchema": {
     "type": "object",
-    "oneOf": [
-      {
-        "properties": {
-          "id": {
-            "type": "string",
-            "description": "Resource ID"
-          }
-        },
-        "required": ["id"]
+    "properties": {
+      "id": {
+        "type": "string",
+        "description": "Resource ID"
       },
-      {
-        "properties": {
-          "name": {
-            "type": "string",
-            "description": "Resource name"
-          }
-        },
-        "required": ["name"]
+      "name": {
+        "type": "string",
+        "description": "Resource name"
       }
-    ]
+    },
+    "oneOf": [{ "required": ["id"] }, { "required": ["name"] }]
   }
 }
diff --git a/schema/draft/schema.json b/schema/draft/schema.json
index 213c58f6d..0b9ba317f 100644
--- a/schema/draft/schema.json
+++ b/schema/draft/schema.json
@@ -3638,7 +3638,7 @@
                 },
                 "inputSchema": {
                     "additionalProperties": {},
-                    "description": "A JSON Schema object defining the expected parameters for the tool.\n\nTool arguments are always JSON objects, so `type: \"object\"` is required at the root.\nBeyond that, any JSON Schema 2020-12 keyword may appear alongside `type` — including\ncomposition keywords (`oneOf`, `anyOf`, `allOf`, `not`), conditional keywords\n(`if`/`then`/`else`), reference keywords (`$ref`, `$defs`, `$anchor`), and any other\nstandard validation or annotation keywords.\n\nProperty schemas may carry an `x-mcp-header` annotation to mirror the\nargument value into an HTTP header on the Streamable HTTP transport. See\nthe Streamable HTTP transport specification for the validity and\nextraction rules.\n\nDefaults to JSON Schema 2020-12 when no explicit `$schema` is provided.",
+                    "description": "A JSON Schema object defining the expected parameters for the tool.\n\nTool arguments are always JSON objects, so `type: \"object\"` is required at the root.\nBeyond that, any JSON Schema 2020-12 keyword may appear alongside `type` — including\ncomposition keywords (`oneOf`, `anyOf`, `allOf`, `not`), conditional keywords\n(`if`/`then`/`else`), reference keywords (`$ref`, `$defs`, `$anchor`), and any other\nstandard validation or annotation keywords.\n\nWhen using composition keywords, declare `properties` at the schema root and keep the\nbranches to presence assertions such as `required`. A subschema that fails on a type\nerror is indistinguishable from one that does not apply, so type constraints placed\ninside `oneOf` branches are not enforced for whichever branch does not match.\n\nProperty schemas may carry an `x-mcp-header` annotation to mirror the\nargument value into an HTTP header on the Streamable HTTP transport. See\nthe Streamable HTTP transport specification for the validity and\nextraction rules.\n\nDefaults to JSON Schema 2020-12 when no explicit `$schema` is provided.",
                     "properties": {
                         "$schema": {
                             "type": "string"
diff --git a/schema/draft/schema.ts b/schema/draft/schema.ts
index b2119e148..669aedeec 100644
--- a/schema/draft/schema.ts
+++ b/schema/draft/schema.ts
@@ -1965,9 +1965,15 @@ export interface ToolAnnotations {
  * @example With no parameters
  * {@includeCode ./examples/Tool/with-no-parameters.json}
  *
+ * @example With a composition input schema
+ * {@includeCode ./examples/Tool/tool-with-composition-input-schema.json}
+ *
  * @example With output schema for structured content
  * {@includeCode ./examples/Tool/with-output-schema-for-structured-content.json}
  *
+ * @example With an array output schema
+ * {@includeCode ./examples/Tool/tool-with-array-output-schema.json}
+ *
  * @category `tools/list`
  */
 export interface Tool extends BaseMetadata, Icons {
@@ -1987,6 +1993,11 @@ export interface Tool extends BaseMetadata, Icons {
    * (`if`/`then`/`else`), reference keywords (`$ref`, `$defs`, `$anchor`), and any other
    * standard validation or annotation keywords.
    *
+   * When using composition keywords, declare `properties` at the schema root and keep the
+   * branches to presence assertions such as `required`. A subschema that fails on a type
+   * error is indistinguishable from one that does not apply, so type constraints placed
+   * inside `oneOf` branches are not enforced for whichever branch does not match.
+   *
    * Property schemas may carry an `x-mcp-header` annotation to mirror the
    * argument value into an HTTP header on the Streamable HTTP transport. See
    * the Streamable HTTP transport specification for the validity and