Agent Instructions
Preserve useful judgment in guidance a future agent can find and apply. A skill earns its place through knowledge, preferences, or recurring failures the agent would otherwise miss. More instructions are not evidence of progress.
Find the instruction's owner
Use dialectic when the purpose or desired behavior is unsettled: articulate the proposed model alongside a sample of the behavior it would produce. Use reactions to both to develop the instructions. Settled edits do not require another discovery conversation.
Ground the guidance in actual work, source material, or the user's corrections. Extract the judgment behind an accepted interaction, not its topic, layout, or turn count. Remove instructions that push against that judgment before adding compensating rules. An example is evidence for a principle, not a template for every future response.
Update the existing owner when the intent is the same. Create a separate skill when it offers a coherent capability someone would reach for independently. Merge or delete guidance whose distinction creates more work than it saves; legitimate composition does not require every phrase to have exactly one owner.
Keep cross-task constraints in AGENTS.md, specialized judgment in skills, and architecture or decision history in the relevant README or ADR. References carry conditional detail; scripts carry repeated fragile mechanics. One-off advice and rules already owned elsewhere need not become another instruction.
Write for judgment
State the premise and connect instructions to their reasons so the agent can apply them to cases you did not anticipate. Give criteria and boundaries; prescribe a sequence only when the order affects correctness. Keep enough context to prevent the recurring mistake without dictating unrelated work.
Describe the capability and the user intent that should select it in the frontmatter description. Add exclusions for plausible near misses, and revisit the description when the capability changes. The body supplies the judgment and workflow rather than repeating a list of trigger phrases.
Keep the core readable on its own. Link to a reference with a concrete reason to read it, and retain examples only when they reveal something the principle cannot carry alone. Remove obsolete references and duplicated rules as part of the same edit; moving every paragraph elsewhere is not simplification.
Repository conventions
Project skills live in .agents/skills/<name>/SKILL.md with lowercase hyphenated
names and YAML frontmatter containing name and description. Preserve optional
metadata or host settings unless the requested change makes them unnecessary;
do not add host scaffolding to portable skills by default.
For skills intended for Claude as well, create a relative sibling link from the repository root, and update or remove it with the skill:
bashln -s ../../.agents/skills/<name> .claude/skills/<name>
Codex-only skills deliberately have no Claude link. CLAUDE.md files are shims importing the sibling AGENTS.md. Durable personal guidance belongs in the tracked dotfiles repository, not a host-managed system-skill installation.
When importing guidance, inspect its scripts, dependencies, external actions, and assumptions before using them. Adapt to local conventions and state the tools or credentials the workflow needs; instructions cannot grant access.
Check what changed
Choose checks that answer a concrete uncertainty. Check affected links after moving references; check frontmatter and intended-host discovery after changing skill names, locations, or discovery metadata. A prose correction does not by itself require an installation CLI or an audit of the whole library.
Review the motivating request and a materially different use to see whether the judgment transfers, including when direct action is appropriate. When behavior is uncertain or regresses, compare actual work with the previous version, or without the skill for a new capability. Report what was observed separately from what the wording is intended to improve.
Read evaluation when investigating selection or behavior, comparing versions, or asked for evidence of improvement. Read composition diagnostics when checking broken links, duplicated guidance, or competing skill descriptions. Neither is a required pass for every edit.
