LLM evals that stay current as your product evolves
The core problem with agent evals is not that they are hard to write. It is that they go stale. Static datasets and manual annotation age out faster than a team can maintain them. Tessary synthesizes the eval pipeline from your codebase and recalibrates it on production traces, so the suite tracks the product instead of decaying behind it.
- Stay current
- Re-synthesis runs as your code, prompts, and models change.
- No leak
- No manual curation step that goes stale the moment you skip it.
- Grounded
- Calibrated on your production traces, not synthetic data.
Static evals were built for slow-moving software.
The eval playbook most teams inherited assumes the thing under test changes slowly. Agents do not. When prompts, models, and orchestration shift every week, any approach with a manual maintenance step quietly stops reflecting the product.
- Faster
agent-based products change faster than the software the eval playbook was written for: prompts, models, and orchestration all shift weekly
- Stale
golden datasets, manual annotation, and dashboard uploads age out faster than a team can maintain them
- A leak
any eval approach that depends on a manual curation step quietly stops reflecting the product the moment someone gets busy
Synthesize, calibrate, re-synthesize, curate
The pipeline is generated from the product and kept current automatically. The only standing human job is curation, and that work compounds.
Synthesize from the current codebase
Tessary reads your repo as it is today: every model call, what each one is for, and how it can fail. The eval pipeline is generated from the product, not maintained by hand alongside it.
Calibrate on live traces
Graders are tuned against real production spans, so they reflect the inputs your agent actually sees rather than a frozen sample from launch week.
Re-synthesize as the product moves
When prompts, models, or orchestration change, synthesis re-runs. New call sites get graders, retired ones drop out, and the taxonomy follows the product instead of lagging it.
Curate to compound
Your accept, reject, and edit decisions persist across re-syntheses. The eval suite gets sharper over time instead of decaying.
An eval suite that gets sharper, not staler
Evals generated from code
The pipeline is derived from your codebase, so it tracks the product instead of drifting away from it.
Re-synthesis on change
Every model upgrade, prompt change, or refactor triggers a fresh pass, so coverage does not rot between releases.
Calibrated on real traffic
Graders are tuned on production traces, so the bar for pass and fail matches how your agent is actually used.
A failure taxonomy that grows
A hierarchical map of how your product fails, specific to you, that compounds with every curation decision.
Curation that persists
Your edits survive re-synthesis, so the work you put in last month still counts after the product changes.
Transparent and portable
Read every grader, run them on your own keys, and keep them if you ever leave.
Questions about evals that evolve
Related pages
Evals for agentic products
The overview: synthesized eval pipelines that evolve with your agent.
Regression detection
Catch breakage from any change, judged against a baseline.
Evals for the CTO
For the person who owns agent quality and gets paged when it breaks.
The agent evals SDK
Wire graders into your agentic workflow and run them on every change.
Stop maintaining evals by hand.
Connect your code, get a working pipeline, and let it stay current as your agent changes. The graders are transparent, and your curation compounds.