LLMs, GenAI, RAG, agents, evaluation · insight-0639
Score agents on the end state they produce, not on how the transcript reads
- Evidence type
- documented fact
- Difficulty
- medium
- Roles
- Applied AI, Data scientist, ML engineer
- Industries
- aviation, retail
Summary: situation, action, reason, boundary
Situation
Agent evaluation consists of reading transcripts or asking a judge model whether the conversation "looks successful".
Action
For each test task define the expected final state (records created or changed, messages sent, values) and compare the environment after the run with that goal state.
Reason
τ-bench evaluates agents by comparing the database state at the end of a conversation with an annotated goal state, which checks outcomes rather than wording.
Boundary
Tool-using agents that change records, tickets, bookings or files.
Symptom or risk
Polite, plausible transcripts hide wrong database changes: the wrong flight rebooked, a refund issued twice, a policy step skipped.
Exceptions
Purely conversational assistants, where response quality itself is the outcome.
Trade-offs
Needs a resettable test environment with seeded data.
Pitfalls
Checking only the target record and missing collateral changes elsewhere.
Lessons and concepts
Claims and their sources
τ-bench judges agent success by comparing the final database state with the annotated goal state.