Pipeline

Pipeline

The Pipeline pattern organizes tasks into sequential stages, where the output (artifact) of a preceding stage serves as the input instruction/context for the next stage.

5-Stage Workflow

Input ──► [ Stage A ] ──► (Artifacts) ──► [ Stage B ] ──► (Artifacts) ──► Output
            Worker A                       Worker B

1. Definition: Outline the stages, assign specific assistant configurations, and define the handover criteria.
2. Setup: Provide a shared directory path via workspaceOverride so all stages modify the same project directory.
3. Execution:
   • Before each stage, inspect agent__listAgents(type="sessions") for an Idle child with the same assistant ID and a compatible workspace. Reuse it with agent__messageToSession; set reset=true when the stage is a fresh assignment and the prior conversation/runtime state must be discarded.
   • Start a new stage with agent__startSession(..., waitForResult=true) when no suitable child exists, the stage needs a different role or workspace, or the pipeline requires another parallel capacity slot.
   • Collect the output path and stage summary upon completion.
4. Handover: Bind the output paths and preceding summaries into the task prompt of the next stage session.
5. Final Format: Aggregate the final stage's output and present it to the user.

🛠️ MCP Tools Guide

• Session Reuse: Reusing a reset session preserves workspace files but closes its browser session. Treat each stage as runtime-isolated even when the session identity is reused, and do not reuse a child whose workspace contract does not match the stage.
• Sequential Assignments: Use agent__messageToSession with waitForResponse=true for a reused child, agent__startSession with waitForResult=true for a new child, or agent__checkSession(sessionId, wait=true) to synchronize.
• Context Filtering: Avoid passing the entire conversation logs of previous stages to prevent context bloat. Only pass the summarized markdown text and file paths.

See pipeline-specs.md for details.

References

• Pipeline specs
• Handover templates
• Failure recovery