SKILL.md
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Evaluation is iterative. When a score is below threshold, diagnose the cause, fix it, rerun — don't just report the failure.
How to iterate
- Start small: Begin with 1-2 eval cases, not the full suite
- Run eval:
agents-cli eval run
- Read the scores — identify what failed and why
- Fix the code — adjust prompts, tool logic, instructions, or the evalset
- Rerun eval — verify the fix worked
- Repeat steps 3-5 until the case passes
- Only then add more eval cases and expand coverage
Expect 5-10+ iterations. This is normal — each iteration makes the agent better.
Task tracking: When doing 5+ eval-fix iterations, use a task list to track which cases you've fixed, which are still failing, and what you've tried. This prevents re-attempting the same fix or losing track of regression across iterations.
Shortcuts That Waste Time
Recognize these rationalizations and push back — they always cost more time than they save:
Shortcut
Why it fails
"I'll tune the eval thresholds down to make it pass"
Lowering thresholds hides real failures. If the agent can't meet the bar, fix the agent — don't move the bar.
"This eval case is flaky, I'll skip it"
Flaky evals reveal non-determinism in your agent. Fix with temperature=0, rubric-based metrics, or more specific instructions — don't delete the signal.
"I just need to fix the evalset, not the agent"
If you're always adjusting expected outputs, your agent has a behavior problem. Fix the instructions or tool logic first.
What to fix when scores fail
Failure
What to change
tool_trajectory_avg_score low
Fix agent instructions (tool ordering), update evalset tool_uses, or switch to IN_ORDER/ANY_ORDER match type
response_match_score low
Adjust agent instruction wording, or relax the expected response
final_response_match_v2 low
Refine agent instructions, or adjust expected response — this is semantic, not lexical
rubric_based score low
Refine agent instructions to address the specific rubric that failed
hallucinations_v1 low
Tighten agent instructions to stay grounded in tool output
Agent calls wrong tools
Fix tool descriptions, agent instructions, or tool_config
Agent calls extra tools
Use IN_ORDER/ANY_ORDER match type, add strict stop instructions, or switch to rubric_based_tool_use_quality_v1
Choosing the Right Criteria
Goal
Recommended Metric
Regression testing / CI/CD (fast, deterministic)
tool_trajectory_avg_score + response_match_score
Semantic response correctness (flexible phrasing OK)
final_response_match_v2
Response quality without reference answer
rubric_based_final_response_quality_v1
Validate tool usage reasoning
rubric_based_tool_use_quality_v1
Detect hallucinated claims
hallucinations_v1
Safety compliance
safety_v1
Dynamic multi-turn conversations
User simulation + hallucinations_v1 / safety_v1 (see references/user-simulation.md)
Multimodal input (image, audio, file)
tool_trajectory_avg_score + custom metric for response quality (see references/multimodal-eval.md)
For the complete metrics reference with config examples, match types, and custom metrics, see references/criteria-guide.md.
Running Evaluations
# Scaffolded projects — agents-cli:
agents-cli eval run --evalset tests/eval/evalsets/my_evalset.json
# With explicit config file:
agents-cli eval run --evalset tests/eval/evalsets/my_evalset.json --config tests/eval/eval_config.json
# Run all evalsets in tests/eval/evalsets/:
agents-cli eval run --all
**agents-cli eval run options:** --evalset PATH, --config PATH, --all
Compare two result files:
agents-cli eval compare baseline.json candidate.json
Configuration Schema ( eval_config.json )
Both camelCase and snake_case field names are accepted (Pydantic aliases). The examples below use snake_case, matching the official ADK docs.
Full example
{
"criteria": {
"tool_trajectory_avg_score": {
"threshold": 1.0,
"match_type": "IN_ORDER"
},
"final_response_match_v2": {
"threshold": 0.8,
"judge_model_options": {
"judge_model": "gemini-flash-latest",
"num_samples": 5
}
},
"rubric_based_final_response_quality_v1": {
"threshold": 0.8,
"rubrics": [
{
"rubric_id": "professionalism",
"rubric_content": { "text_property": "The response must be professional and helpful." }
},
{
"rubric_id": "safety",
"rubric_content": { "text_property": "The agent must NEVER book without asking for confirmation." }
}
]
}
}
}
Simple threshold shorthand is also valid: "response_match_score": 0.8
For custom metrics, judge_model_options details, and user_simulator_config, see references/criteria-guide.md.
EvalSet Schema ( evalset.json )
{
"eval_set_id": "my_eval_set",
"name": "My Eval Set",
"description": "Tests core capabilities",
"eval_cases": [
{
"eval_id": "search_test",
"conversation": [
{
"invocation_id": "inv_1",
"user_content": { "parts": [{ "text": "Find a flight to NYC" }] },
"final_response": {
"role": "model",
"parts": [{ "text": "I found a flight for $500. Want to book?" }]
},
"intermediate_data": {
"tool_uses": [
{ "name": "search_flights", "args": { "destination": "NYC" } }
],
"intermediate_responses": [
["sub_agent_name", [{ "text": "Found 3 flights to NYC." }]]
]
}
}
],
"session_input": { "app_name": "my_app", "user_id": "user_1", "state": {} }
}
]
}
Key fields:
intermediate_data.tool_uses— expected tool call trajectory (chronological order)
intermediate_data.intermediate_responses— expected sub-agent responses (for multi-agent systems)
session_input.state— initial session state (overrides Python-level initialization)
conversation_scenario— alternative toconversationfor user simulation (seereferences/user-simulation.md)
Common Gotchas
The Proactivity Trajectory Gap
LLMs often perform extra actions not asked for (e.g., google_search after save_preferences). This causes tool_trajectory_avg_score failures with EXACT match. Solutions:
- **Use
IN_ORDERorANY_ORDERmatch type** — tolerates extra tool calls between expected ones
- Include ALL tools the agent might call in your expected trajectory
- Use
rubric_based_tool_use_quality_v1instead of trajectory matching
- Add strict stop instructions: "Stop after calling save_preferences. Do NOT search."
Multi-turn conversations require tool_uses for ALL turns
The tool_trajectory_avg_score evaluates each invocation. If you don't specify expected tool calls for intermediate turns, the evaluation will fail even if the agent called the right tools.
{
"conversation": [
{
"invocation_id": "inv_1",
"user_content": { "parts": [{"text": "Find me a flight from NYC to London"}] },
"intermediate_data": {
"tool_uses": [
{ "name": "search_flights", "args": {"origin": "NYC", "destination": "LON"} }
]
}
},
{
"invocation_id": "inv_2",
"user_content": { "parts": [{"text": "Book the first option"}] },
"final_response": { "role": "model", "parts": [{"text": "Booking confirmed!"}] },
"intermediate_data": {
"tool_uses": [
{ "name": "book_flight", "args": {"flight_id": "1"} }
]
}
}
]
}
App name must match directory name
The App object's name parameter MUST match the directory containing your agent:
# CORRECT - matches the "app" directory
app = App(root_agent=root_agent, name="app")
# WRONG - causes "Session not found" errors
app = App(root_agent=root_agent, name="flight_booking_assistant")
The before_agent_callback Pattern (State Initialization)
Always use a callback to initialize session state variables used in your instruction template. This prevents KeyError crashes on the first turn:
async def initialize_state(callback_context: CallbackContext) -> None:
state = callback_context.state
if "user_preferences" not in state:
state["user_preferences"] = {}
root_agent = Agent(
name="my_agent",
before_agent_callback=initialize_state,
instruction="Based on preferences: {user_preferences}...",
)
Eval-State Overrides (Type Mismatch Danger)
Be careful with session_input.state in your evalset. It overrides Python-level initialization:
WRONG — initializes feedback_history as a string, breaks .append():
"state": { "feedback_history": "" }
CORRECT — matches the Python type (list):
"state": { "feedback_history": [] }
Model thinking mode may bypass tools
Models with "thinking" enabled may skip tool calls. Use tool_config with mode="ANY" to force tool usage, or switch to a non-thinking model for predictable tool calling.
Common Eval Failure Causes
Symptom
Cause
Fix
Missing tool_uses in intermediate turns
Trajectory expects match per invocation
Add expected tool calls to all turns
Agent mentions data not in tool output
Hallucination
Tighten agent instructions; add hallucinations_v1 metric
"Session not found" error
App name mismatch
Ensure App name matches directory name
Score fluctuates between runs
Non-deterministic model
Set temperature=0 or use rubric-based eval
tool_trajectory_avg_score always 0
Agent uses google_search (model-internal)
Remove trajectory metric; see references/builtin-tools-eval.md
Trajectory fails but tools are correct
Extra tools called
Switch to IN_ORDER/ANY_ORDER match type
LLM judge ignores image/audio in eval
get_text_from_content() skips non-text parts
Use custom metric with vision-capable judge (see references/multimodal-eval.md)
Deep Dive: ADK Docs
For the official evaluation documentation, fetch these pages:
- Evaluation overview:
https://adk.dev/evaluate/index.md
- Criteria reference:
https://adk.dev/evaluate/criteria/index.md
- User simulation:
https://adk.dev/evaluate/user-sim/index.md
Debugging Example
User says: "tool_trajectory_avg_score is 0, what's wrong?"
- Check if agent uses
google_search— if so, seereferences/builtin-tools-eval.md
- Check if using
EXACTmatch and agent calls extra tools — tryIN_ORDER
- Compare expected
tool_usesin evalset with actual agent behavior
- Fix mismatch (update evalset or agent instructions)
Proving Your Work
Don't assert that eval passes — show the evidence. Concrete output prevents false confidence and catches issues early.
- After running eval: Paste the scores table output so the user can see exactly what passed and failed.
- After fixing a failure: Show before/after scores for the specific case you fixed, and confirm no other cases regressed.
- Before declaring "eval passes": Confirm ALL cases pass, not just the one you were working on. Run
agents-cli eval run(oragents-cli eval run --all) one final time.
- Before moving to deploy: Show the final
agents-cli eval runoutput with all cases above threshold. This is the gate — no exceptions.
Related Skills
/google-agents-cli-workflow— Development workflow and the spec-driven build-evaluate-deploy lifecycle
/google-agents-cli-adk-code— ADK Python API quick reference for writing agent code
/google-agents-cli-scaffold— Project creation and enhancement withagents-cli scaffold create/scaffold enhance
/google-agents-cli-deploy— Deployment targets, CI/CD pipelines, and production workflows
/google-agents-cli-observability— Cloud Trace, logging, and monitoring for debugging agent behavior