spec-implement

A step in a spec-driven development workflow that turns a broad project phase plan into detailed implementation work. It uses project specifications and technical reference documents to guide the changes.

In plain words
What is it for?
Selecting the next incomplete phase, detailing its plan, implementing it, and recording the resulting decisions and status in project documentation.
Why use it?
It connects planned requirements with concrete files, database structures, endpoints, and implementation steps. It also updates the specification so it matches the finished code.

Command

Install

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.

agentmods
npx agentmods add commands/connorrmcd6/vibe-spec/spec-implement
Clone the repo
git clone --depth 1 https://github.com/Connorrmcd6/vibe-spec
Per session 36 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 650 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00036 $0.00650
Opus 5 $0.00018 $0.00325
Sonnet 5 $0.00007 $0.00130
Haiku 4.5 $0.00004 $0.00065

Measured 2d ago against content hash eb7448f876c6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

spec-implement 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.

commands/spec-implement.md · 41 lines

What it actually says

You are running Step 5 of the Vibe-Spec spec-driven workflow: detailing and implementing one phase. This step is iterative — run it once per phase, ideally in a fresh session. See the vibe-spec skill (${CLAUDE_PLUGIN_ROOT}/skills/vibe-spec/reference/00-workflow.md).

What to do

  1. Load context. Read docs/project-spec.md (the V2 spec) and the target phase's plan file under docs/plans/. Pick the phase from $ARGUMENTS, or default to the next phase whose status isn't Complete. Also read the previous phase's plan so decisions carry forward.
  2. Promote to detailed. Expand the phase plan from High-level to Detailed: concrete files, schema, endpoints, and steps. Update the header's Detail level to Detailed and Status to In Progress. For each stack area, consult the matching vibe-spec reference file and follow its conventions and gotchas exactly (e.g. 01-scaffolding.md for project setup, 05-prisma.md for schema, 07-auth.md for auth, 08-rbac.md for roles, 10-testing.md for tests).
  3. Implement the detailed plan. Use official CLI/init commands for boilerplate wherever possible (pnpm create next-app, pnpm prisma init, shadcn init).
  4. Update the docs — this is not optional. If anything drifted during implementation (design changes, bottlenecks, skipped or added features), update the phase doc so it reflects reality, and update dependent phase docs and the V2 spec where needed. Capture decisions made, not just TODOs. A stale spec is worse than no spec — it actively misleads future sessions. Set the phase Status to Complete when done.
    • Govern the docs (if the project uses Surface). For any domain whose logic this phase changed, add or update the relevant hub claim, then — once you've confirmed the prose is true — run surf verify to re-seal it so the pre-commit surf check gate stays green. New invariant worth governing? Author a fresh claim with surf new / surf suggest. See reference/20-surface.md. This makes "keep the docs honest" a mechanical gate, not just a good intention.

End by summarizing what changed and telling the user to start a fresh session and run /spec-implement for the next phase. If new phases became necessary, add them with /spec-phases conventions and continue.

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 First seen · 41 lines · 36 tokens per session scan A eb7448f876c6

Subscribe to this mod's changes

spec-implement is a command published in the GitHub repository Connorrmcd6/vibe-spec (9 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 650 once invoked, about $0.0002 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.