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Inspect an agent repository and optional traces, interview the user, write reviewed Task Specs, build and audit Harbor tasks, and bootstrap reusable project World Knowledge Skills. Use for agent evals, benchmark design, Task generation, controlled Environments, synthetic data, Verifiers, Harbor runs, calibration, or continuous benchmark maintenance.

Use this Skill: https://skilld.dev/gh/langchain-ai/langchain-skills/eval-engineering

This session only. Nothing lands on disk.

referencestask-implementation.md

≈2.1k tokens on demand. Your agent reads this file only when SKILL.md points to it.

Implement and Audit a Task

This is the concrete implementation guide for Spec2Task. Use it after the user selects a Task and reviews its collocated Task.md. The result is a runnable Harbor Task whose Environment, Verifier, and real-run evidence match that Task Spec.

Contents

Read references at each decision

Current decision Read Required output
What state, service, access, fidelity, or trial isolation to build Environment building Environment contract and setup or isolation method recorded in Task.md
How to create structured records or natural-language content Synthetic data Materialized data, validation evidence, and generation review when used
What evidence proves success and how failures score Verifier design Pass rule, criteria, independent evidence, and focused fixtures
How to package, configure, and run the Task Harbor Runnable task source, resolved configuration, and retained job evidence
How to inspect traces and judge fairness Calibration Run classifications, defects, rerun results, and remaining uncertainty
How to preserve reusable project knowledge World knowledge World Skill additions, corrections, or an explicit decision that none are reusable

Read only the references required by the current Task, but do not implement a layer before reading the reference that defines its checks.

Build in this order

1. Synchronize the Task files

Create instruction.md from the exact agent input in Task.md. Normally this input has explicit approval. If the human requested an end-to-end build with no approval pause, implementation can use the agent-reviewed Draft input, but Task.md must remain Status: Draft. Create the complete package defined in Harbor: task.toml, instruction.md, a usable Environment definition, and tests/test.sh, plus only the optional Verifier helpers, fixtures, and reference solution the Task needs. Check that later turns, access, time limits, and invalid-run conditions match the Task Spec.

Read the project World Skill used during design. Add or correct only reusable knowledge supported by the current implementation work. Keep the exact request, focal records, expected result, hidden truth, and exact scoring rules in Task.md.

2. Build the Environment

Follow Environment building. Preserve the production interface used by the Harness. Implement only the services, files, records, permissions, errors, and state changes needed by this Task. Keep hidden truth and raw Verifier access unavailable to the evaluated agent. Update the World Skill when this work proves a reusable project setup, service, state, access, or isolation method.

3. Build and validate data

When the Task needs constructed data, follow Synthetic data. Create IDs, relationships, permissions, dates, and constraints with code. Use a model only for fields that need natural language. Materialize the accepted data so every trial uses the same reviewed input. Update the World Skill when the method, schema, relationship rule, or validator can support another Task.

4. Build the Verifier

Follow Verifier design. Implement objective checks from raw files, tests, database state, service state, or other independent evidence. Use a model judge only for bounded semantic meaning that code cannot settle. Keep judge instructions, credentials, and expected results outside the Harness boundary. Update the World Skill when this work proves a reusable independent evidence source, accepted alternative, or known scoring risk.

5. Package the Harbor Task

Follow the package-completeness audit in Harbor. Confirm that every required file, entry point, path, permission, configuration value, mount, service, dependency, and reward output needed to run the exact Task exists and works through Harbor. Confirm hidden Task, Verifier, solution, and secret material is absent from the agent-visible image and workspace. Fix every gap before any Oracle or model trial. Then confirm the model, trial count, judge, timeout, and maximum expected cost with the human unless that run plan is already authorized.

Check setup and trial isolation

Reset means returning mutable state to the Task's declared starting condition before another trial uses it. It is an infrastructure concern, not a score of Task quality. Choose the check that matches the Environment:

Environment Appropriate check
Fresh disposable container, VM, or worktree per trial Build one fresh trial and verify its declared starting state. Replacement provides isolation.
Mutable service or database reused across trials Capture Task-relevant starting state, make a representative change, run reset, and confirm the starting state returns.
Immutable frozen files, corpus, or repository Verify the pinned source loads correctly. No reset test is needed.
Approved live sandbox Verify the dedicated identity, safe starting state, allowed effects, and cleanup method. Do not use production writes.

Create or compare another fresh trial only when nondeterminism, shared state, or flaky setup is a real risk. Record expected runtime differences only when they cannot affect agent behavior or scoring.

Run deterministic checks

Before a model run:

  1. Call every operation the Task needs and confirm its response and effect.
  2. Confirm relevant invalid actions fail for the intended reason.
  3. Run the reference path when one exists to prove the Task is reachable.
  4. Run Verifier fixtures for a known-good result, a different valid result, a realistic wrong result, a shortcut, a prohibited collateral change, and missing or corrupt evidence.
  5. Confirm wrong work receives zero and infrastructure faults receive no agent score.
  6. Confirm every completed Verifier path writes criterion evidence and reward.

Fix deterministic failures before spending a model call. These checks establish reachability and Verifier behavior. They do not by themselves prove that the Task has the intended difficulty or realism.

Run and inspect the Harness

Run the actual Harness through Harbor. Follow Calibration. Read the complete selected trajectories, initial and final state, Verifier evidence, service logs, resolved configuration, phase timing, and errors.

Classify each bad outcome before changing anything. Keep a fair capability failure as an agent result. Repair missing information, Harness defects, Environment defects, false acceptance, false rejection, leakage, and infrastructure failure, then rerun the affected trial.

Revise the correct layer

Evidence shows Change
The request is unclear or unfair instruction.md and Task.md
Required state is missing or unrealistic Environment implementation and its description in Task.md
A valid result fails or invalid result passes Verifier and its fixtures
Tools, prompts, sessions, or adapters differ from the intended agent Harness or adapter
Startup, timeout, credential, judge, or cleanup fails Harbor or runtime configuration; keep the old run unscored

For a material Task Spec change, set Task.md to Draft, show the diff, and require explicit reapproval before marking it Approved again.

Finish by reconciling reusable knowledge

After the Task passes its audit, follow World knowledge and reconcile the World Skill already used during design and implementation. Keep supported project-specific knowledge that can help another Task. Narrow or remove claims that the audit disproved. Keep the current Task's exact request, focal state, expected result, hidden truth, and scoring criteria in its Task directory. Show the final World Skill changes with the audit results.

Source: SKILL.md on GitHub

1 warning1mo3 checks · Risk SAFE
  • Gen Agent Trust Hub1mo

    This skill provides a framework for engineering and auditing AI agent evaluations using Harbor and LangSmith. It includes security considerations for managing external service credentials and executing code within isolated Docker environments, which are essential to its intended purpose of evaluation and testing.

  • Socket1mo

    No alerts

  • Snyk1mo

    Risk: MEDIUM · 1 issue

Signed by skilld at fc20103. This ties the file your Agent reads to that commit on GitHub. It does not review the instructions.

Last checked against GitHub 2 days ago.

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