Skill Claude CodeCodex
Give an agent access to many tools without flooding its context with every tool definition. Covers the three advanced-tool-use patterns: a search tool the agent calls to discover tools on demand, programmatic tool calling where the model writes code that invokes tools and filters results before they return, and…
Skill Claude CodeCodex
Ship a change to a running agent without degrading it, and keep a long-running agent reliable. Covers gating every system-prompt or model change behind a broad eval run, rolling out in stages and watching for report spikes, treating the agent's reasoning or thinking state as an invariant a cache must not drop, giving…
Skill Claude CodeCodex
Audit an agent for risky behavior before it ships, the way you would red-team it, but automated. An auditor agent runs many multi-turn scenarios against your target agent from seed instructions you write, and a judge model scores the transcripts for deception, sycophancy, oversight subversion, power-seeking, and…
Skill Claude CodeCodex
Build automated evaluations for an AI agent from scratch: collecting tasks from real failures, choosing code/model/human graders, picking pass@k vs pass^k, building an isolated harness, and keeping the suite honest over time. Use this whenever someone wants to measure, benchmark, or regression-test an agent, write an…
Skill Claude CodeCodex
Stop the machine from deciding your benchmark. Configure and validate the container and runtime resources for an agentic coding eval so infrastructure noise stays inside statistical bounds instead of swinging scores more than the models do. Use this whenever someone runs SWE-bench or any agentic coding benchmark in…
Skill Claude CodeCodex
Design the tool interface for a coding agent so the model stops misusing it. Covers the minimal two-tool scaffold (a bash tool plus a file editor), exact single-match string replacement, absolute-path rules, and error-proofing the tool descriptions so common model mistakes become impossible. Use this whenever someone…
Skill Claude CodeCodex
Screen an agent's input and output against a policy you write, so it refuses the content classes you disallow without over-refusing the ones you allow. Covers writing a constitution that lists allowed and disallowed content for your app, screening user input before the model and model output before delivery…
Skill Claude CodeCodex
Keep an agent from obeying instructions hidden in the content it reads. Covers placing fetched pages, emails, and API responses in toolresult blocks instead of the system prompt; wrapping that content as JSON with explicit source fields; labeling its provenance; screening tool output with a fast classifier before the…
Skill Claude CodeCodex
Structure a long-lived agent service so any part can crash and resume. Decompose it into brain (model plus harness), hands (ephemeral sandbox and tools), and session (a durable event log), each replaceable on its own, with wake/resume semantics and credentials kept out of the execution environment. Use this whenever…
Skill Claude CodeCodex
Run an orchestrator-worker system for breadth-first research: a lead agent plans, spawns three to five subagents with their own context windows, and synthesizes their findings. Covers when multi-agent actually beats a single agent and when it just burns tokens, how to delegate so subagents do not overlap…
Skill Claude CodeCodex
Coordinate several unsupervised agents working on one shared git repo without collisions. Covers the autonomy loop that lets each agent pick the next task and respawn without a human, file-based lock files that claim work, machine- readable test output so a test suite steers the agents instead of a person, and context…
Skill Claude CodeCodex
Keep an agent from gaming a checkable objective instead of doing the work. An agent told to make tests pass may delete the failing test, hard-code the expected output, or special-case the grader; the task looks done and its intent is defeated. Covers spotting reward-hacking in transcripts and evals, inoculation…
Skill Claude CodeCodex
Contain an agent that runs code or reads untrusted content, layer by layer. Covers OS-level filesystem and network isolation that also catches spawned subprocesses, an egress proxy that checks request provenance, treating tool outputs and fetched pages as prompt-injection vectors, and keeping credentials outside the…
Skill Claude CodeCodex
Decide where an agent should reason during a task and how to prompt for it. Covers three places a model can think and how to choose between them: extended thinking before the turn, interleaved thinking between tool calls, and the no-op "think" tool that logs reasoning mid-chain at a point you pick. Also covers when a…