Stop your agents from failing silently.

Built for engineers running agents in production, Tessary watches every trace, catches what broke, and shows you why.

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on Tessary Cloud · 10,000 traces a month · no credit card required

116: traces emitted in the last hour
3: sampled and evaluated
1: wrong, raised by a customer

how it works

Monitor every trace, not a sample.

Your agent already emits spans. Tessary reads all of them as they land – no sampling, no LLM call.

Filter down to what broke.

Twelve traces break the same way. Tessary groups them into one case.

Analyze them against your code.

We read the failing traces against your repo and find the change that explains it.

Know what to change.

You get the cause and the evidence behind it, minutes after the first bad trace.

case 1184 · checkout agent · 12 of 218 tracesreading repository…

tools/refund.py · changed in a1f9c2

11def resolve_refund(order, cust):

12payload = {"order": order.id}

13cust never reaches the payload

14return client.refund(payload)

all 12 failing traces hit line 13 · no healthy trace does

The refund payload lost customer_id.

12payload = {"order": order.id}

13payload["customer_id"] = cust.id

case: checkout agent · tool-call errors increased
change: 0.4% → 11.2% in four hours
affected traces: 218
likely cause: tool argument changed in commit a1f9c2
next step: restore customer_id in the refund payload

features

Observability
Monitor every production trace to understand how your agents behave over time.
Classifiers
Check every trace against focused conditions to detect failures, behavioral drift, and users frustrated with your agent.
Cases
Turn validated issues into cases your team can investigate, track, and resolve.
RCA
Trace issues to their root cause across prompts, tools, models, and agent code.

pricing

Free to run. Talk to us when you need more.

Open Source

self-host or Tessary Cloud

Free

no credit card required

Every production trace, monitored
Built-in classifiers for drift, tool errors, secret leaks, malformed output, frustration and groundedness
Cases, triage and root-cause analysis
Cloud: 10,000 traces a month, 30-day retention, $10 credit

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Paid

self-host or managed hosting

Let's talk

priced per customer

Everything in Free
Custom classifiers: describe a failure in plain words, and our agent builds a classifier for your real production traces
Managed hosting: a dedicated instance, run by us
Higher limits, longer retention, support over a dedicated Slack channel

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