Coding Posture

Task-aware working modes for coding agents. One SKILL.md file: before non-trivial work, the agent picks a mode — debug, fix, review, test-first, refactor, optimize, migrate, upgrade, integrate, spike, unstuck — and follows its checklist.

It exists to stop agents from behaving like optimistic elevators with write access: thrashing on a stuck bug, faking green tests, skipping reproduction, running destructive commands, migrating without a rollback.

Works with Hermes · Claude Code · Codex · Cursor · Pi — any SKILL.md-compatible agent.

How the agent uses it

flowchart TD
    Task["Non-trivial coding task"] --> Pick{"Pick a mode that fits<br/>(debug, fix, review, migrate, …)"}
    Pick -->|no match| Normal["Proceed normally"]
    Pick -->|match| Check["Follow the mode's checklist"]
    Check --> Loop["gather context → localize → smallest change<br/>→ run the real check → read output"]
    Loop --> V{"Verified by a real run?"}
    V -->|no| Loop
    V -->|yes| Done(["Done"])
    Guard["Always-on invariants:<br/>no fake green · no destructive commands · don't game tests"] -.->|guards every step| Check
    Guard -.-> Loop

Modes

Always — in every mode:

• Verify by running the real check (test, build, repro); never by re-reading.
• Never report a result you didn't run; never weaken, delete, or game a test to go green.
• No destructive commands (force push, reset --hard, drop, rm -rf) without explicit scope.

Install

Install as a plugin (one command, updates in place) or drop the skill in directly. It's a standard SKILL.md skill, so it works unmodified across compatible agents.

Claude Code — plugin

/plugin marketplace add alexei-led/coding-posture
/plugin install coding-posture@coding-posture

Update later with /plugin marketplace update coding-posture then /reload-plugins, or enable auto-update from the /plugin menu to refresh on startup.

Codex CLI — plugin

git clone [email protected]:alexei-led/coding-posture.git
codex   # then: /plugins → add the local marketplace in ./coding-posture → install coding-posture

Or point Codex straight at the skill in ~/.codex/config.json:

{ "skills": ["/abs/path/to/coding-posture/skills/coding-posture"] }

Update later with git pull.

Other agents

The agent activates the skill from its description when a coding task starts.

How it works — theory and evidence

A skill is just text placed in the model's context. A worked procedure acts as an in-context demonstration: the model conditions its next tokens on the shown trajectory, not just the final answer — the same basis as chain-of-thought. No complete mechanistic theory of frontier-model reasoning exists yet, so treat this as a grounded substrate, not a proof.

Each design claim, and how strong the evidence actually is:

Two deliberate consequences:

• Procedures, not personas. A persona ("act as an expert debugger") sets style; a procedure supplies structure the model can follow. So each mode is a checklist, not a character.
• Small on purpose. Instruction-following degrades as a prompt grows long and complex, so a short, followable procedure beats a long aspirational one. (The popular "~150–200 instructions" ceiling has no peer-reviewed source; the real effect is just degradation with length.)

Where this fits

Frontier agents already do the basics (reproduce bugs, run tests, small diffs), and a good CLAUDE.md/AGENTS.md repeats them. This skill earns its place only as the delta — the anti-instincts agents get wrong by default (stop thrashing, don't game the grader, roll back before migrating, measure before optimizing, read the API contract) — plus a mode catalog too large to keep always-on.

Split the rules by how often they must fire:

Anthropic's skill guidance is evaluation-driven: keep only what measurably closes a gap.

Try it

Open source — clone it, drop the skill into your agent, and watch how it changes the work. In the behavioral eval (eval/) the skill scores 85% vs 70% without it (+15pp), with the urgent-auth case going 4/4 vs 2/4. Run the eval on your own model and tasks, open an issue with what you find, or add a mode — contributions welcome.