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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
docs	Skipped		Jun 23, 2026 4:42am

PR Summary

High Risk
Touches credentials (BYOK-only keys in sandboxes, GitHub tokens, SSH), remote code execution (E2B + user machines), and git push/PR automation with deliberate secret-handling complexity that needs careful review.

Overview
Introduces a Pi Coding Agent workflow block that runs the Pi harness against a real repo, with Cloud (E2B sandbox, git clone/push, draft PR) and Local (SSH-scoped read/write/bash, optional Sim integration tools) modes. Execution is wired through a new PiBlockHandler with shared skills/memory from the Agent block, filtered model options, streaming output, and extensive unit tests.

Cloud adds E2B_PI_TEMPLATE_ID, withPiSandbox, and a build script for a Pi+git E2B image; the cloud backend isolates GitHub vs model API keys per command, writes prompts/commits via sandbox files (not shell), and hardens git steps against repo-planted config.

Local embeds @earendil-works/pi-coding-agent (externalized in Next/Trigger) with SSH repo tools and executeTool-backed Sim tools; MCP/custom tools are blocked via new unsupportedToolTypes on tool-input (greyed UI + tooltips on the Pi block).

Docs add pi.mdx to Core Blocks; minor change sets default User-Agent on custom tool HTTP calls.

^{Reviewed by Cursor Bugbot for commit c7b1d4e. Configure here.}

Greptile Summary

This PR introduces the Pi Coding Agent block, a new executor that runs the Pi harness against a real repository in either cloud mode (E2B sandbox → GitHub clone → PR) or local mode (SSH into the user's own machine). It wires a new PiBlockHandler into the executor registry, adds a corresponding block definition with credential fields, and reuses the Agent block's skills and memory subsystems.

• Cloud backend (cloud-backend.ts): clones a repo into an isolated E2B sandbox, runs the Pi CLI in JSON-streaming mode, then stages/commits/pushes and opens a PR. Secret isolation is well-designed: the GitHub token is scoped only to the clone and push steps (and stripped from the remote between them), while the Pi loop runs with only the model key.
• Local backend (local-backend.ts): loads the Pi SDK dynamically, opens a single reused SSH connection and SFTP channel for the run, exposes read/write/edit/bash tools confined to the configured repo path, and captures the working-tree diff over the same session.
• Key resolution (keys.ts): enforces BYOK-only for cloud mode (model key goes into an untrusted sandbox), allows hosted keys for local mode mirroring the Agent block.

Confidence Score: 5/5

Safe to merge; no correctness or data-integrity issues found on the changed paths

The two backends are well-isolated (BYOK enforcement, per-command secret scoping, SSH connection and temp-dir cleanup correctly guarded). The only findings are two dead/premature checks in the cloud backend and a || vs ?? edge case in token accumulation — none affect run correctness in practice.

cloud-backend.ts has the dead isBYOK guard and the vertex-wastes-sandbox path; events.ts has the || vs ?? accumulation issue

Important Files Changed

Sequence Diagram

%%{init: {'theme': 'neutral'}}%%
sequenceDiagram
    participant UI as Block UI
    participant H as PiBlockHandler
    participant K as keys.ts
    participant CB as CloudBackend
    participant LB as LocalBackend
    participant E2B as E2B Sandbox
    participant SSH as SSH Session

    UI->>H: execute(inputs)
    H->>K: resolvePiModelKey(model, mode)
    K-->>H: "{providerId, apiKey, isBYOK}"

    alt Cloud mode
        H->>CB: runCloudPi(params, context)
        CB->>E2B: withPiSandbox()
        CB->>E2B: CLONE_SCRIPT (GITHUB_TOKEN scoped here only)
        CB->>E2B: writeFile(pi-prompt.txt)
        CB->>E2B: PI_SCRIPT (model key only, no GITHUB_TOKEN)
        CB->>E2B: PREPARE_SCRIPT (no secrets)
        CB->>E2B: PUSH_SCRIPT (GITHUB_TOKEN scoped here only)
        CB->>CB: openPullRequest via executeTool
        CB-->>H: "{totals, changedFiles, diff, prUrl}"
    else Local mode
        H->>LB: runLocalPi(params, context)
        LB->>SSH: openSshSession()
        LB->>LB: loadPiSdk() + createAgentSession()
        LB->>SSH: read/write/edit/bash tools
        LB->>SSH: captureRepoChanges()
        SSH-->>LB: "{changedFiles, diff}"
        LB-->>H: "{totals, changedFiles, diff}"
    end

    H->>H: appendPiMemory()
    H-->>UI: BlockOutput (content, tokens, cost, diff, prUrl)

%%{init: {'theme': 'base', 'themeVariables': {"darkMode": true, "background": "#0d1117", "primaryColor": "#21262d", "primaryTextColor": "#e6edf3", "primaryBorderColor": "#8b949e", "lineColor": "#8b949e", "textColor": "#e6edf3", "edgeLabelBackground": "#161b22", "actorBkg": "#21262d", "actorBorder": "#8b949e", "actorTextColor": "#e6edf3", "actorLineColor": "#8b949e", "signalColor": "#8b949e", "signalTextColor": "#e6edf3", "noteBkgColor": "#373320", "noteBorderColor": "#d4a72c", "noteTextColor": "#f0e6c0", "labelBoxBkgColor": "#21262d", "labelBoxBorderColor": "#8b949e", "labelTextColor": "#e6edf3", "loopTextColor": "#e6edf3", "activationBkgColor": "#30363d", "activationBorderColor": "#8b949e"}}}%%
sequenceDiagram
    participant UI as Block UI
    participant H as PiBlockHandler
    participant K as keys.ts
    participant CB as CloudBackend
    participant LB as LocalBackend
    participant E2B as E2B Sandbox
    participant SSH as SSH Session

    UI->>H: execute(inputs)
    H->>K: resolvePiModelKey(model, mode)
    K-->>H: "{providerId, apiKey, isBYOK}"

    alt Cloud mode
        H->>CB: runCloudPi(params, context)
        CB->>E2B: withPiSandbox()
        CB->>E2B: CLONE_SCRIPT (GITHUB_TOKEN scoped here only)
        CB->>E2B: writeFile(pi-prompt.txt)
        CB->>E2B: PI_SCRIPT (model key only, no GITHUB_TOKEN)
        CB->>E2B: PREPARE_SCRIPT (no secrets)
        CB->>E2B: PUSH_SCRIPT (GITHUB_TOKEN scoped here only)
        CB->>CB: openPullRequest via executeTool
        CB-->>H: "{totals, changedFiles, diff, prUrl}"
    else Local mode
        H->>LB: runLocalPi(params, context)
        LB->>SSH: openSshSession()
        LB->>LB: loadPiSdk() + createAgentSession()
        LB->>SSH: read/write/edit/bash tools
        LB->>SSH: captureRepoChanges()
        SSH-->>LB: "{changedFiles, diff}"
        LB-->>H: "{totals, changedFiles, diff}"
    end

    H->>H: appendPiMemory()
    H-->>UI: BlockOutput (content, tokens, cost, diff, prUrl)

_{Reviews (3): Last reviewed commit: "fix tests" | Re-trigger Greptile}

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