Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/willackerly/rebar/rebar-coldstartnpx skills add willackerly/rebar --skill rebar-coldstartgit clone --depth 1 https://github.com/willackerly/rebarWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00071 | $0.00470 |
| Opus 5 | $0.00036 | $0.00235 |
| Sonnet 5 | $0.00014 | $0.00094 |
| Haiku 4.5 | $0.00007 | $0.00047 |
Grade A, and why
rebar-coldstart 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.
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.
What it actually says
rebar-coldstart — the session-start ritual
Canonical practice: rebar:practice/session-lifecycle (Session Start section)
— resolve with scripts/rebar-doc.sh rebar:practice/session-lifecycle --cat
(or rebar doc if the CLI is installed).
This skill is a pointer to the ritual, not a replacement for the practice doc.
Steps
- Read the cold-start quad:
QUICKCONTEXT.md,TODO.md,CLAUDE.md(orAGENTS.mdwhere that is the agent-facing doc), and recent reality —git log --oneline -15. - Look for the hook output. A
SessionStarthook (configured in.claude/settings.json) runsscripts/cold-start-checks.shand injects a<rebar-cold-start>…</rebar-cold-start>block into your first turn. If the block is present, read it — it is harness ground truth, not prose. - No block? Run it yourself. On harnesses without hooks (or before the
hook is installed), run
scripts/cold-start-checks.shmanually and read its output. Missing block = missing hook; say so. - Cross-check freshness. Compare QUICKCONTEXT claims against
git log; if its last-synced date is >1 week old, treat all claims as suspect and verify before acting. - Coordination seats only: if this repo holds a peer
inbox/, sweep it first (ls -lat inbox/ | head), then armscripts/inbox-watch.shas a persistent background monitor — see therebar-inbox-watchskill.
Do not start substantive work until steps 1–4 are done.
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.
- 2d ago First seen · 33 lines · 71 tokens per session scan A 2f8493425d17
rebar-coldstart is a skill published in the GitHub repository willackerly/rebar (5 stars, last pushed 20d ago), licensed Apache-2.0. It adds 71 tokens to every session and 470 once invoked, about $0.0004 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.
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