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Entries 1–20 of 52
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A Coding Agent That Writes Its Own Tests Is Grading Itself
When a coding agent writes both the change and the tests, a passing suite measures the agent's idea of done. Treat it as an eval problem: tests written from the spec, exit codes, rendered measurements and a named human verdict.8 min readcoding-agentsagent-evaluation
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Read an Agent Architecture Diagram by Tracing Every Arrow to Code
A box labeled trusted budget means nothing if its arrow carries a field the model wrote. Trace each arrow in an eval agent's diagram to the line of code that reads it.10 min readagent architecturesystem design
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Shadow-Test an Agent Release Without Duplicate Writes
An agent release is a tuple of model, prompt, tools and config. Run the candidate in shadow on real inputs with its write authority removed, and derive how many clean episodes it takes to bound what you missed.9 min readshadow deploymentagent releases
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Measure Whether One Tool Schema Works Across Model Providers
The same JSON Schema can be offered to two providers and still produce different calls, costs and refusals. Keep one strict contract, write thin adapters, and run a paired experiment before you call the tool portable.8 min readtool-callingmodel providers
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Test an Agent's Fallback Path Against the Same Acceptance Bar
A fallback model runs rarely, so production traffic barely measures it and the aggregate hides it. Derive why, then force failover on your eval set and grade the fallback against the primary's contract.8 min readfallback modelsagent-evaluation
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Use a Circuit Breaker When Retries Multiply an Outage
With r retries at each of d layers, one request can become (r + 1)^d sends, and the multiplier peaks exactly when the dependency is down. Derive it, simulate it, and see what a shared breaker changes.12 min readcircuit breakerretry amplification
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Reserve an Agent's Spending Before Each Request, Not After
A counter in one process cannot stop eight workers from spending the same last dollar. Bound each call's maximum charge, reserve it atomically in a shared ledger, settle from real usage, and test the race.12 min readagent cost controlinference-cost
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Roll Back an Agent Release as a Whole Tuple, Not One File
Reverting the prompt alone can leave an old prompt talking to a new tool. Treat model, prompt, tools and config as one release tuple, roll back to a tuple you evaluated, and keep irreversible effects in their own ledger.7 min readagent releasesrollback
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Give Every Agent Memory an Owner, a Source Revision and an Expiry Rule
A stored fact goes stale when time passes or when its source changes. Record who owns it and which revision it came from, select the current fact by rule rather than similarity, and escalate conflicts.7 min readagent-memorymemory-lifecycle
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Check What a Citation Proves: Provenance Versus Entailment
An exact, byte-matched quote proves where text came from, not that it supports the claim. Test provenance and entailment separately, and compare exact match, NLI and an LLM judge.8 min readcitation verificationresearch agents
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Find the Failing RAG Stage Before You Change the Prompt
Measured on SciFact with small open models: attribute each miss to retrieval, reranking, prompt assembly or generation, then change only the stage that failed. A targeted prompt fix took 107 correct to 151.10 min readRAG retrieval evaluationrecall-at-k
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Turn a Grading Policy Into a Test Table, Then Mutate the Grader
Write boundary cases for an eval grader from its policy, compute expected results by hand, then break the grader on purpose to prove every row can fail. Seven mutants, seven kills.9 min readevaluationmutation testing
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Keep Enough Trace Detail to Grade and Reproduce an Agent Run
A truncated agent transcript can look like a clean success. Record what a trial needs for grading and replay, mark truncation explicitly, and size how many transcripts to read.9 min readagent transcriptstrajectory review
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Capture Agent Trajectories for Evals Without Copying User Data
Agent traces are the raw material for evals, and production traces carry user data. Capture structure by default, keep content in a restricted store, test every serialization path with canaries, and bound leaks by sampling.8 min readagent tracesagent-evaluation
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Cancel an Eval Run or Agent Job Without Misreporting What Ran
A canceled eval run still has requests in flight, bills for them, and leaves a biased partial score. Name the states, count the in-flight work with Little's law, and report only what the evidence supports.10 min readagent cancellationevaluation runs
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Recheck What a Human Approved at the Moment the Agent Acts
An approval is a check; the agent's action is the use. Close the time-of-check-to-time-of-use gap: bind approval to exact state, estimate how often it goes stale, and make the final check atomic.9 min readhuman approvalTOCTOU
What an AI Agent Remembers After a Restart
After a restart, an agent remembers what your application stored and nothing else. Run a short Python example on Colab that loses its conversation and keeps a corrected preference.7 min readagent-memoryagent state design
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When a Tool Fails, Return a Typed Error, Not an Empty List
An experiment-tracker timeout that returns [] tells your agent no prior runs exist. Keep failure and emptiness apart with typed results, a mutation test, and a protocol to measure the damage.10 min readtool useerror handling
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Split Agent Tools by Effect, Then Measure the Unsafe-Call Rate
A tool whose name hides a destructive branch makes the dispatcher's job and the model's job harder. Split tools by effect class, then measure merged against split under injection, with intervals.7 min readtool-designagent-evaluation
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