Agent Reliability

As the CTO, you own agent quality. Tessary tells you what broke it.

You have an agent in production at real volume, and your name is on whether it works. Today you learn a flow broke from a customer, and the why takes days to dig out. Tessary watches grader verdicts as a trend, catches the drop, and walks it back to the change responsible, in time to fix it before it costs you an account.

For
CTOs and eng leads with an agent already serving real production volume.
Owns
Quality. You get paged when the agent breaks, and asked why later.
Edge
The cause, named. The same read also runs on the PR before a deploy and can gate the merge.
The Problem

Quality lands on you, and the why is the hard part.

The product side feels the drop first, and your team gets asked why. That is the same split Sentry serves, and Tessary answers for both. It starts with watching the agent across the changes that actually move it.

16%

of Sonnet 4 requests were misrouted at the worst hour of a routing bug that ran from early August into September 2025. Anthropic wrote afterward: "The evaluations we ran simply didn't capture the degradation users were reporting."

Anthropic postmortem, 2025

89%

of 1,340 survey respondents have observability in place, but only 52.4% run offline evaluations. Watching dashboards is common. Knowing why a score moved is not.

LangChain State of Agent Engineering, 2025

5%

of all LLM call spans reported an error in February 2026. The rest of what went wrong returned cleanly, so nothing in your error budget moves while a flow quietly degrades.

Datadog, State of AI Engineering 2026

How It Works

From a manual review you own to a cause you can point at

Land your traffic, watch the graders as a trend, route the alerts, and when something drops, get the change behind it.

  1. Land your production traffic

    Push traffic in via the OTLP receiver (gen_ai OpenTelemetry) with the TypeScript or Python SDK, or connect Langfuse or Braintrust as an upstream source and start from the traces you already collect. This is built for an agent with volume, not a prototype.

  2. Watch quality as a trend, not a dashboard

    Graders score real traffic on the dimensions your product depends on: task completion, groundedness, tone. Detection reads the trend across verdicts over time rather than any single score, so an imperfect grader still catches a real change; it misfires at a stable rate, and a jump from 3% to 11% is a genuine shift.

  3. Route alerts where the team already is

    Digests, briefs, and threshold alerts go to Slack, Sentry, PagerDuty, Linear, or a webhook, so a regression stops depending on one person remembering to look. Before a deploy, a GitHub Action reads the PR diff, maps the touched surface to the failure families most likely to fire (tool-call errors, refusal spikes, hallucinated citations), and can gate the merge.

  4. Get the cause, not just the page

    When a grader trend breaks, Tessary traces the failing quality dimension back through the agent's chain to the change that caused it: a prompt edit, a tool update, a dependency bump, an upstream agent's shift, or a provider model update that never touched your repo. Commit-SHA lineage covers the ones that did.

What You Get

Built for the constraints you actually have

Cause-finding on production drops, a pre-deploy read on risky changes, provider independence, and lineage you can audit.

Risk read before the merge

The diff classifier and change-history risk model post a pre-deploy trouble report on the PR, and the GitHub Action can block the merge. A gate only fires on changes that ship through a PR, so production detection stays on for the causes that never touch your repo.

Quality you can delegate

Regressions surface as grader verdicts on real traffic and alerts in Slack or PagerDuty, so agent quality is a team default instead of a manual review you personally own.

Works with your existing stack

Already on Langfuse or Braintrust? Connect either as an upstream source and start from the traces you already collect. When a cause hunt hits a gap in those traces, that gap is the next node worth instrumenting, and the next hunt gets further.

Provider independence

Your agent can run across multiple model providers, and the reliability platform works across them and across trace stacks too.

One graph for monitoring and evals

Eval verdicts and production behavior live on one graph, versioned by commit. When a score drops, you walk straight from the failing grader to the production traces behind it, and to the change behind those.

Lineage you can audit

Every run ties back to what produced it: the commit, the prompt version, the tool version, and the model that served the turn. When the question about a broken flow comes to you, you point at the change, not guess.

FAQ

Questions CTOs ask about agent reliability

A CTO or engineering lead at an SMB with traction, with an agent already in production at real volume. It is for the person who owns quality and gets paged when the agent breaks, not for a pre-product team still shaping a first prototype.
Observability tools and eval platforms like Langfuse and Braintrust tell you a score moved. Tessary tells you why, and which change moved it. When a grader trend breaks, it traces the failing quality dimension back through the agent's chain to the cause, including changes that never show up in a diff. The same read also runs on the PR before a merge, so a risky change is flagged before the deploy.
Push it in through the OTLP receiver using gen_ai OpenTelemetry conventions, with the TypeScript or Python SDK. If you are already instrumented on Langfuse or Braintrust, connect it as an upstream source and pull a slice on demand instead of re-instrumenting.
Graders flag failure modes on real traffic, and digests, briefs, and threshold alerts route to the channels your team already triages in. The alert carries the attribution with it: the failing dimension and the change the trend break traces back to, so the thread starts at the cause instead of at a dashboard.
No. Ingest and graders work across model providers and trace stacks, and verdicts stay comparable regardless of which provider served the turn. That matters for attribution too: when one provider updates a model underneath you, the drop shows up in the trend and traces back to that provider change, not to your last deploy.
Get Started

Make agent quality a system, not a fire drill.

Land the traffic from your production agent, and the next time a flow degrades you get the cause named, in time to fix it before a customer writes in. Starting needs your traffic and no credit card.

Find what broke your agentPush traffic via OTLP, or connect Langfuse or Braintrust as an upstream source.