LLMs, GenAI, RAG, agents, evaluation · insight-0641
Report steps, tool calls and tokens per task alongside agent success rate
- Evidence type
- practitioner heuristic
- Difficulty
- easy
- Roles
- Applied AI, ML engineer, Data scientist
- Industries
- cross-industry
Summary: situation, action, reason, boundary
Situation
Two agent designs reach similar task success, and the comparison stops there.
Action
Log per run the number of inference calls, tool calls, input and output tokens and wall-clock time; report their distribution (median and 90th percentile) for successful and failed runs.
Reason
Agent success is a ratio of outcomes; trajectory length is a separate cost and risk signal. OpenTelemetry's GenAI conventions define counts of inference and tool calls per agent invocation for this purpose.
Boundary
Agent design comparisons and release gates.
Symptom or risk
One design needs three times more model calls and tool calls per task, so it is slower, costlier and has more chances to hit a failing dependency.
Exceptions
Very early prototypes, where only feasibility matters.
Trade-offs
More metrics invite cherry-picking; agree on the decision metric beforehand.
Pitfalls
Looking at means only; agent trajectories are long-tailed.
Lessons and concepts
Claims and their sources
OpenTelemetry's GenAI metric conventions (status Development) include the number of inference calls and tool calls made during an agent invocation.