gemini-cli/.gemini/skills/behavioral-evals/SKILL.md

name, description

name	description
behavioral-evals	Guidance for creating, running, fixing, and promoting behavioral evaluations. Use when verifying agent decision logic, debugging failures, debugging prompt steering, or adding workspace regression tests.

Behavioral Evals

Overview

Behavioral evaluations (evals) are tests that validate the agent's decision-making (e.g., tool choice) rather than pure functionality. They are critical for verifying prompt changes, debugging steerability, and preventing regressions.

Note

Single Source of Truth: For core concepts, policies, running tests, and general best practices, always refer to evals/README.md.

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🔄 Workflow Decision Tree

1. Does a prompt/tool change need validation?
   • No -> Normal integration tests.
   • Yes -> Continue below.
2. Is it UI/Interaction heavy?
   • Yes -> Use appEvalTest (AppRig). See creating.md.
   • No -> Use evalTest (TestRig). See creating.md.
3. Is it a new test?
   • Yes -> Set policy to USUALLY_PASSES.
   • No -> ALWAYS_PASSES (locks in regression).
4. Are you fixing a failure or promoting a test?
   • Fixing -> See fixing.md.
   • Promoting -> See promoting.md.

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📋 Quick Checklist

1. Setup Workspace

Seed the workspace with necessary files using the files object to simulate a realistic scenario (e.g., NodeJS project with package.json).

• Details in creating.md

2. Write Assertions

Audit agent decisions using rig.setBreakpoint() (AppRig only) or index verification on rig.readToolLogs().

• Details in creating.md

3. Verify

Run single tests locally with Vitest. Confirm stability locally before relying on CI workflows.

• See evals/README.md for running commands.

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📦 Bundled Resources

Detailed procedural guides:

• creating.md: Assertion strategies, Rig selection, Mock MCPs.
• fixing.md: Step-by-step automated investigation, architecture diagnosis guidelines.
• promoting.md: Candidate identification criteria and threshold guidelines.