feat(mcp): run saved project scripts by juliusmarminge · Pull Request #8714 · pingdotgg/t3code

juliusmarminge · 2026-08-30T00:53:41Z

Problem

Agents can manage project script definitions through the project MCP surface, but they cannot discover or run a saved script through the managed terminal lifecycle.

Change

Add bounded saved-script discovery, run a saved script ID in a caller-named fresh terminal, and stop only the matching managed run. Ownership is bound to the terminal incarnation and is released by terminal lifecycle events.

Behavior

Script cwd and runtime environment come from the target thread and project. Run and stop reuse #8707's serialized full-access/default authorization boundary. Callers cannot supply command text, host paths, environment variables, or preview actions. A removed or renamed script definition does not prevent stopping its existing run; close, restart, exit, and terminal-ID reuse invalidate the old run handle. Opening plus ownership registration is interruption-safe, while the operation remains honestly non-idempotent. A queued exit preserved across clear releases ownership before the terminal ID is reused.

Focused validation

deterministic real Manager/fake-PTY proof that exit queued before clear reaches exited state, invalidates script ownership, and permits safe terminal-ID reuse
62 focused Manager, terminal MCP, and saved-script tests for the latest cross-layer fix
original production registration, contract, policy, cwd/environment, partial-failure, and lifecycle validation remains in this layer

Dependency

Upper layer of native stack #8715. Depends on #8707 for scoped terminal resolution, strict fresh creation, terminal-incarnation handles, bounded output, event-drain serialization, and lifecycle controls; the stack is rooted on immutable rollout base agents/mcp-controls/base-490318a.

Implemented by GPT-5.6-Sol via Codex in T3 Code.

Note

Add MCP tools to list, run, and stop saved project scripts

Adds ProjectScriptMcpService and a three-tool MCP toolkit (t3_project_script_list, t3_project_script_run, t3_project_script_stop) registered on the MCP HTTP server and advertised in orchestration capabilities via savedProjectScripts.
Listing returns paginated, bounded command previews with length and truncation metadata. Running opens a fresh owned terminal, writes the saved command, and returns either accepted-input or opened-but-input-failed outcomes. Stopping requires matching project, script, terminal, and incarnation ownership before closing.
Extends TerminalManager with admitRunningSessionHandle (atomic ownership under the thread lock) and subscribeSessionInvalidation (notifies on close, restart, replacement, or exit) so the service drops stale ownership.
Adds contract schemas in projectScriptMcp.ts with bounded inputs, validated result/failure types, and barrel exports.
Adds t3_project_script_list to the Claude read-only MCP allowlist in ClaudeAdapterV2.ts; run and stop are excluded because they mutate.
Risk: TerminalManager interface gains two required operations (admitRunningSessionHandle, subscribeSessionInvalidation); out-of-tree implementations of this interface must add both methods.

^{Macroscope summarized 7c7bdd6.}

Note

Medium Risk
Run/stop execute saved commands in real PTYs under the same host-execution boundary as terminal MCP, and TerminalManager’s public interface gains two required methods that mocks must implement.

Overview
Agents can discover and execute project scripts through MCP without supplying arbitrary shell input. The PR adds t3_project_script_list, t3_project_script_run, and t3_project_script_stop, wired through a new ProjectScriptMcpService and registered on the HTTP MCP server alongside existing toolkits.

Listing returns paginated script metadata with bounded command previews. Run opens a fresh owned terminal (caller-chosen terminalId), writes the saved command plus Enter, and records script/run ownership tied to the terminal incarnation. Stop closes only when project, script id, terminal id, and handle still match; ownership is dropped on close, restart, exit, or session invalidation. Run/stop inherit the same full-access / default interaction policy as other terminal mutations; list is read-only.

TerminalManager gains admitRunningSessionHandle (atomic ownership registration under the thread lock) and subscribeSessionInvalidation (notify when an incarnation is replaced). Orchestrator capabilities advertise savedProjectScripts; Claude’s read-only MCP allowlist adds t3_project_script_list only. Contracts, UI tool labels, and user docs are updated accordingly.

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coderabbitai · 2026-08-30T00:53:49Z

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github-actions · 2026-08-30T00:58:10Z

Thread transfer impact

⚠️ The latest CI run did not produce a thread transfer result for 7c7bdd6.

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macroscopeapp · 2026-08-30T01:00:51Z

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — This PR introduces a production MCP workflow for running and stopping saved project scripts, including new terminal ownership and lifecycle handling across shared server infrastructure. Its user-facing execution capability and cross-component runtime impact warrant human review.

Notes:

Diff unchanged. Approvability was decided on eligibility alone.

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macroscopeapp

Effect service conventions review of the new ProjectScriptMcpService and its contracts/toolkit modules. One convention violation found; everything else (Context.Service tag with inline interface, make/layer ordering and naming, environment-based dependency acquisition, namespace subpath imports, test seams) matches the conventions.

^{Posted via Macroscope — Effect Service Conventions}

cursor

Cursor Bugbot has reviewed your changes using high effort and found 1 potential issue.

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juliusmarminge marked this pull request as ready for review August 30, 2026 00:53

github-actions Bot added vouch:trusted PR author is trusted by repo permissions or the VOUCHED list. size:L 100-499 changed lines (additions + deletions). labels Aug 30, 2026

juliusmarminge mentioned this pull request Aug 30, 2026

feat(mcp): control managed terminals #8707

Closed