The scaffolding that makes agents reliable.

Evaluation suites

Graded datasets, LLM-as-judge with calibrated rubrics, regression tests that run on every commit and every model upgrade.

Observability

Span-level tracing for every tool call, prompt, and retry. Cost, latency, and quality surfaced on one dashboard your on-call engineer can actually read.

Orchestration

Deterministic control flow around non-deterministic models. Retry strategies, fallback chains, circuit breakers, and budget caps.

Guardrails

Input validation, output schemas, PII redaction, and policy enforcement — layered so no single failure mode reaches the customer.

Prompt & tool versioning

Every prompt, every tool schema, every eval run is versioned, diffable, and rollback-able. Deploys feel like deploys, not prayers.

Drift detection

When model behavior shifts — provider side, temperature side, your side — you know within an hour, not a quarter.

An eval that runs on every commit.

One-liner at the top of your PR check. Evals are graded against your labeled dataset; regressions gate merge. No prompt gets pushed to main without passing the same bar your production run held yesterday.

Everything we build is yours. No proprietary SDK lock-in — just Python (or Go, or TS) your team can read, extend, and audit.

from apex import Suite, judge, gate

# Load 412 labeled production incidents
suite = Suite.from_jsonl("data/incidents.jsonl")

@suite.check(threshold=0.95)
def routes_correctly(case, agent_output):
    return agent_output.route == case.expected_route

@suite.check(threshold=0.99)
def no_hallucinated_systems(case, agent_output):
    return judge(
        agent_output.narrative,
        rubric="cites only systems in case.registry",
    )

# Fail the build if any check regresses
gate(suite.run(agent="triage@v7"))

Silent regressions, customer-facing hallucinations, inference bills that climb without explanation.

You ship prompts based on a handful of manual checks. You know this is bad. You don't have time to fix it.

Orchestration, shared observability, and unified eval infra before the portfolio gets unmanageable.

Model behavior shifted, evals didn't catch it, you found out from a customer. Harness prevents the next one.

Two ways in.

Book a call or read our writing. We don't run sales cadences — if there's a fit we'll say so.