Polaris: Skill for Claude Code

.agents/skills/spec-contract/SKILL.md

spec-contract is a skill for Claude Code, Codex from sponge-b0b/Polaris. It costs 26 tokens per session (4,799 once invoked), scanned A, original, Apache-2.0.

An internal helper that lists the exact requirements a Spec must satisfy and identifies which changes belong to that Spec.

In plain words
What is it for?
Use it to build or validate the requirement record used when checking and reviewing a Spec.
Why use it?
It prevents verification and review tools from using different requirement lists or confusing older integration work with current work.

Skill for Claude CodeCodex

Written for Claude Code and Codex: disable-model-invocation in frontmatter, but also agents/openai.yaml present. Also seen: positional $N argument; installed under .agents/ (shared by several agents); mentions Codex.

This is sponge-b0b/Polaris's own configuration. It tells Claude Code and Codex how to work on Polaris itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything Polaris configures →

Reuse

Borrowing it

Nothing to install: this file belongs to sponge-b0b/Polaris. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/sponge-b0b/Polaris/main/.agents/skills/spec-contract/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/sponge-b0b/Polaris

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for spec-contract

README.md
[![agentmods](https://agentmods.dev/badge/skills/sponge-b0b/polaris/spec-contract.svg)](https://agentmods.dev/skills/sponge-b0b/polaris/spec-contract)
Your own site
<a href="https://agentmods.dev/skills/sponge-b0b/polaris/spec-contract"><img src="https://agentmods.dev/badge/skills/sponge-b0b/polaris/spec-contract.svg" alt="Measured on agentmods" height="20"></a>
Per session 26 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,799 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00026 $0.04799
Opus 5 $0.00013 $0.02400
Sonnet 5 $0.00005 $0.00960
Haiku 4.5 $0.00003 $0.00480

Measured 2d ago against content hash 412653213ac8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

spec-contract scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/classify_ownership.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/spec-contract/SKILL.md · 462 lines

How it starts

The opening of the file, as written. The whole thing — 462 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Spec Contract

$spec-contract is an internal, non-lifecycle helper for $verify-spec and $review-spec.

It owns two shared facts that must not be independently reinvented by those callers:

  1. the complete Spec Contract Manifest of normative obligations;
  2. the complete Spec Change Provenance universe separating branch-local, mixed-provenance, inherited-only, and unchanged/named repository surfaces.

It does not verify implementation, review implementation, create findings, mutate tracker state, edit repository files, commit, push, decide remediation, or decide semantic lifecycle ownership from Git position. A caller-supplied temporary contract-handoff file is permitted working state, not a repository artifact.

Change Provenance Is Not Semantic Ownership

This section is authoritative and supersedes every preserved section below that equates branch-local Git history with Spec-owned or Mixed semantic ownership.

The deterministic provenance helper and this skill may establish only where a repository change sits relative to the fixed Spec baseline, current HEAD, and immutable default-branch head. They must not infer that a change is owned by the current Spec merely because it is reachable only from the Spec branch.

Canonical repository provenance states are:

  • branch-local — changed on the current branch relative to the immutable default-branch head and not also changed by inherited default-branch integration;
  • mixed-provenance — the same surface changed in both inherited default-branch history and current branch-local history;
  • inherited-only — present in fixed-baseline → HEAD integration history but absent from the current branch-local delta;
  • unchanged/named — unchanged by the branch but explicitly named by a Spec obligation or governing authority and therefore potentially relevant to proof.

The complete branch/integration surface universe must be materialized before callers reason about scope. Every provenance candidate must appear in exactly one mechanical provenance state; missing/ambiguous provenance fails closed.

Read the full file on GitHub · 462 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago Changed · +41 lines 412653213ac8
  2. 4d ago Changed · +36 lines 43d5f1ba1671
  3. 8d ago First seen · 385 lines · 26 tokens per session scan A cc1c014c0588

Subscribe to this mod's changes

spec-contract is a skill published in the GitHub repository sponge-b0b/Polaris (4 stars, last pushed today), licensed Apache-2.0. It adds 26 tokens to every session and 4,799 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.