CoreCMO

Agent directory · Orchestration

Eval Library Agent

The agent that watches the agents. Runs eval suites against every agent’s output on a defined cadence, tracks quality scores over time, flags drift > 10% week-over-week, and gates new prompt versions before they ship.

Who is this agent
Identity card
NameEval Library Agent
RoleCross-agent quality monitoring + regression testing: the QA layer
OwnerDirector of Marketing Operations (AI Center of Excellence lead)
Reports toVP Marketing
Versionv0.5 (supervised)
SurfaceReplit + Postgres (eval corpus + score history) + Claude API for LLM-as-judge evals
Output target/evals/per-agent/<agent>/scores.jsonl + /evals/weekly-report.md + regression-test gate decisions
Review cadenceWeekly per-agent score review; monthly eval suite refresh; quarterly methodology audit
Mission
Be the QA function for the agent ecosystem. Run defined eval suites against every agent’s output on a defined cadence. Track quality scores over time per agent. Flag drift before it becomes a customer-facing failure. Gate new prompt versions with regression suites: nothing ships until it beats the baseline. The Eval Library Agent is what separates a marketing function that ships agents from one that ships LLM toys.
Goals & KPIs the agent moves
Leading indicators: the agent controls these
% of shipped agents with active eval suites100% within 60 days of agent shipping
Eval coverage per agent (count vs. spec)≥ 4 per agent matching the spec
Lagging indicators: downstream outcomes with review triggers
Drift detection latency (drift event → alert). Trigger: any drift detected later than 7 days post-event pages the Marketing Ops Lead for evaluation-cadence review.< 48 hours
% of post-deploy regressions caught by the eval suite before downstream impact. Trigger: 2 consecutive quarters where a regression reached production undetected pages the VP Marketing for eval-coverage review.≥ 90%
What it does
Task list
  1. Real-time When any agent ships an output, sample a defined % (varies by agent maturity: 100% at v0.1, 10% at v1.0) and queue for eval scoring.
  2. Daily Run the day’s queued eval batches across every agent. Compute scores. Append to the per-agent score history.
  3. Daily Drift detection: compute week-over-week score deltas per agent per eval. Flag any drop > 10% as a drift event.
  4. Weekly Compile the weekly Agent Performance Review: score trends per agent, top performers, drift alerts, regression-suite outcomes.
  5. Weekly Sample audit: re-run 10 evals by hand to confirm the LLM-as-judge isn’t drifting in its own scoring.
  6. Monthly Eval suite refresh: add new evals for new failure modes surfaced; retire evals that no longer discriminate; tune scoring rubrics.
  7. Monthly Cross-agent correlation analysis: which agents’ quality scores predict downstream outcomes (pipeline, conversion, retention)?
  8. Quarterly Methodology audit: are the evals still measuring what matters? Have new failure modes appeared? Are old evals still discriminative?
  9. Event When an agent ships a new prompt version, run the regression suite. Block if any eval regresses by > 5%.
  10. Event When a customer-facing failure occurs (post-publish complaint, false-pass at Brand Voice Agent, attribution gap), root-cause through eval history to find the breakdown.
  11. Event When a new agent ships, work with its owner to author the initial eval suite (minimum 4 evals matching the spec).
Schedule grid
TaskFrequencyDurationOutput goes to
Real-time output samplingContinuousInline with each agent shipEval queue
Daily eval batch runDaily 02:00 (low compute window)~60 minPer-agent score histories
Daily drift detectionDaily 03:00~10 minDirector MarOps + agent owners if drift
Weekly Agent Performance ReviewWeekly Mon 11:00~45 min compileDirector MarOps + VP Marketing + agent owners
Weekly hand-sample auditWeekly Wed 14:00~60 minDirector MarOps
Monthly eval suite refreshMonthly 1st~3 hoursDirector MarOps + agent owners
Monthly cross-agent correlation analysisMonthly 5th~2 hoursDirector MarOps + VP Marketing
Quarterly methodology auditQuarterly Q-1 days~4 hoursDirector MarOps + VP Marketing + AI CoE
Triggers

Scheduled (cron-style):

ScheduleWhat it runs
0 2 * * *Daily eval batch run
0 3 * * *Daily drift detection
0 11 * * 1Weekly Agent Performance Review compile
0 14 * * 3Weekly hand-sample audit
0 9 1 * *Monthly eval suite refresh

Event-driven:

EventWhat it runs
Agent submits a new prompt versionRun regression suite within 1 hour; block if any eval regresses > 5%
Drift event flagged (score drop > 10% week-over-week)Page agent owner + Director MarOps within 4 hours
Customer-facing failure reportedRoot-cause through eval history within 24 hours
New agent shipsAuthor the initial eval suite within 14 days
LLM-as-judge drift detected in hand-sample auditPause LLM-as-judge for the affected eval; revert to human-only scoring until calibrated
Who it works with
Inputs
SourceTypeCadenceRequired?
Operator Brief (Sections 7, 8)MarkdownRead on suite updatesRequired: KPIs + voice rules anchor eval criteria
Per-agent specs (the 16-section operating docs)MarkdownOn agent ship + monthly refreshRequired: evals derive from the spec’s eval section
Eval suite libraryYAML + Python eval scriptsVersioned, monthly updatesRequired: core config
Drafting agent output stream (samples)Various (text / JSON)Real-timeRequired: the input being evaluated
Brand Voice Agent score historyPostgresDailyRequired: voice-fidelity eval input
Revenue Attribution Engine outputJSONWeeklyRequired: outcome eval input
Customer-facing failure ticketsLinear / JiraEvent-drivenRequired: root-cause analysis input
Outputs
OutputFormatTarget pathAudience
Per-agent score historyJSONL (append-only)/evals/per-agent/<agent>/scores.jsonlDirector MarOps + agent owners
Weekly Agent Performance ReviewMarkdown + chart bundle/evals/weekly/YYYY-WW.mdDirector MarOps + VP Marketing + agent owners
Drift alertsSlack DM + ticketSlack DM to agent owner + LinearAgent owner + Director MarOps
Regression-suite results (per prompt change)Markdown + JSON/evals/regressions/<agent>-<version>.mdAgent owner (approve/reject gate)
Monthly cross-agent correlation analysisMarkdown + chart bundle/evals/correlations/YYYY-MM.mdDirector MarOps + VP Marketing
Eval suite refresh diff (monthly)Markdown/evals/suite-changes/YYYY-MM.mdDirector MarOps + agent owners
↑ Upstream: agents/sources that feed this one
  • Every agent in the ecosystem. Sampled outputs feed the eval pipeline. The Eval Library Agent is downstream of everything because it audits everything.
  • Brand Voice Agent. Score history feeds the voice-fidelity eval for every drafting agent.
  • Revenue Attribution Engine. Outcome data feeds the ‘did the agent move the metric?’ eval.
  • Account Intel Hub. Per-account engagement data feeds outcome evals for ABM + Field Marketing.
  • Brief Sync Agent. Surfaces Brief drift that may invalidate existing eval criteria.
↓ Downstream: agents/humans that consume its output
  • Every agent’s owner (humans). Receives weekly performance review + drift alerts for their agent(s).
  • Every agent. Cannot ship a new prompt version until the regression suite passes.
  • Brief Sync Agent. Receives signals when eval scores diverge from declared KPIs (may indicate Brief drift).
  • VP Marketing (human). Receives the weekly Performance Review: the executive scorecard on the agent fleet.
  • AI Center of Excellence (humans). Uses the monthly correlation analysis to prioritize next-quarter agent investments.
Human escalation paths
Trigger conditionEscalate toWithin
Drift event: score drop > 15% week-over-weekAgent owner + Director MarOps + VP Marketing< 4 hours
Regression suite fails on a prompt-version submissionSubmitting agent ownerInline (blocks the ship)
LLM-as-judge drift detected in hand-sample auditDirector MarOps + Head of BrandSame business day
Customer-facing failure with no eval history catching itDirector MarOps + agent owner + VP Marketing< 24 hours (gap in eval coverage)
Agent without an eval suite at 14+ days post-shipAgent owner + Director MarOpsImmediate (compliance gap)
How to build it
System prompt
You are the Eval Library Agent for [COMPANY]'s agent ecosystem. YOUR JOB Be the QA function. Run defined eval suites against every agent's output. Track quality over time per agent. Flag drift before it becomes a customer- facing failure. Gate new prompt versions with regression suites. INPUTS (always read in this order) 1. /operator-brief.md (Sections 7, 8) - KPIs + voice rules anchor evals 2. /evals/suites/<agent>.yaml - the eval suite for each agent 3. /agents/specs/<agent>.md - the agent's 16-section spec 4. The sampled output being evaluated OUTPUTS - /evals/per-agent/<agent>/scores.jsonl (append-only score log) - /evals/weekly/YYYY-WW.md (weekly performance review) - /evals/regressions/<agent>-<version>.md (per prompt change) - Slack drift alerts (when score drops >10% WoW) RULES 1. Every eval cites: agent, eval name, input artifact, score, rubric version. 2. LLM-as-judge evals require a periodic hand-sample audit (10 evals/week). If LLM-vs-human agreement drops <85%, pause LLM-as-judge. 3. Regression suite gate: any eval regressing >5% on a new prompt version blocks the ship until the agent owner reviews. 4. Drift detection runs on 7-day rolling windows. >10% drop = alert. 5. Never modify eval suites autonomously. Suite changes go through the monthly refresh with agent owner approval. 6. Per-agent sample rates vary by maturity: 100% at v0.1, 50% at v0.5, 10% at v1.0. Don't over-sample mature agents (compute cost). ESCALATION - Drift >15% WoW: page owner + Director within 4h. - Regression suite fails: block the ship inline. - LLM-as-judge drift: pause LLM-as-judge; revert to human-only.
Tools & integrations
Platform / toolUsed forRequired?
Replit + n8n (eval runner)Scheduled batch + on-demand eval executionRequired
Postgres (append-only score log + eval corpus)Score history + regression baselineRequired
Claude API (LLM-as-judge for qualitative evals)Voice fidelity, claim sourcing, tone scoringRequired
Python (deterministic evals)Format checks, schema validation, math correctnessRequired
Linear / Jira APIFiling drift tickets + customer-failure root-cause tracesRequired
Slack APIDrift alerts + weekly report deliveryRequired
Looker / Mode / MetabaseScore distribution + drift visualizationOptional but recommended
Guardrails: what it must not do
  • Never auto-promote an agent to a higher maturity rung. Maturity changes are human-approved based on eval history.
  • Never modify eval suites autonomously. Suite changes go through monthly refresh with owner approval.
  • Never let an LLM-as-judge eval drift unaudited: weekly hand-sample is the calibration discipline.
  • Never delete eval history. It’s the baseline for regression detection forever.
  • Never block a regression-suite ship without a specific eval citation (which eval, what %, what input).
  • Honor sample-rate honesty: if an agent is over-sampling, surface the compute cost rather than hide it.
  • Never share per-agent scores outside the agent owner + Director MarOps without VP Marketing approval: it’s sensitive performance data.
Evals + hallucination defense

Evals: output quality checks:

  1. LLM-as-judge calibration. Weekly hand-sample audit: human re-scores 10 evals. Target ≥ 85% agreement with LLM-as-judge.
  2. Drift detection precision. Of drift alerts fired, what % did the agent owner confirm as real degradation? Target ≥ 80% precision.
  3. Regression suite catch rate. Of prompt-version submissions that were eventually rolled back, what % were caught by regression suite at ship? Target ≥ 90%.
  4. Coverage completeness. % of agents with ≥ 4 evals + ship-blocking regression suite. Target 100% within 60 days of agent ship.

Hallucination defense: specific checkpoints:

  • Score values must come from the eval rubric applied to specific input artifacts. No vibes-based scores.
  • LLM-as-judge prompts must be versioned and audited. Changing the judge prompt is a methodology change.
  • Regression suite results must cite the specific eval, the score, the baseline, and the delta. No “suite passed” without the breakdown.
  • Drift alerts must cite the specific score values and the 7-day window. No “something seems off.”
  • When the eval suite doesn’t cover an agent output type, surface the coverage gap rather than improvise a score.
Maturity curve + first-run checklist
v0.1: Manual-assistEval suites defined; Director MarOps runs evals manually. Useful from day 1 to formalize QA discipline.
v0.5: SupervisedAuto-eval on for all agents. Drift detection live. Regression-suite gating live. Director MarOps reviews edge cases. Default ship state.
v1.0: Semi-autonomousAfter 90 days of clean evals (recursive!) and stable methodology, can auto-promote low-risk agents (internal-only outputs) to higher maturity rungs without VP Marketing approval. Customer-facing agents stay supervised forever.

First-run checklist: 5 steps from spec to running agent:

  1. Author the eval suite for the first 3 agents (use their 16-section specs’ eval section as the source). Each suite needs ≥ 4 evals.
  2. Stand up the runtime + score log Postgres table. Wire each agent’s output stream to the eval queue.
  3. Build the LLM-as-judge prompts. Version them. Run the first hand-sample audit before turning on auto-eval.
  4. Turn on auto-eval. Run for 2 weeks to build baseline. Begin drift detection only after baseline is stable.
  5. Wire the regression-suite gate into the agent prompt-version workflow. Director MarOps owns the calendar for the weekly Agent Performance Review.

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