spec-implement

A workflow for implementing a planned coding task, called a work item, from a project's active task list.

In plain words
What is it for?
It selects an appropriate work item, reads its feature context, updates its progress, writes the code, and verifies the result.
Why use it?
It gives developers a defined way to choose unfinished work, read its requirements, and continue work already in progress without duplicating tasks.

Skill for Claude CodeCodex

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 skills/schmidthole/serf/spec-implement
Any agent
npx skills add schmidthole/serf --skill spec-implement
Clone the repo
git clone --depth 1 https://github.com/schmidthole/serf

Made for: Claude Code, Codex.

Per session 27 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,395 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 $0.00027 $0.01395
Opus 5 $0.00014 $0.00698
Sonnet 5 $0.00005 $0.00279
Haiku 4.5 $0.00003 $0.00139

Measured 2d ago against content hash da196f461e1e, 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.

skills/spec-implement/SKILL.md · 97 lines

How it starts

The opening of the file, as written. The whole thing — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.

reference

read development-workflow.md for the full conventions governing the specs directory structure, features, work items, and their formats.

instructions

pick up and implement a work item, or resume one that is already in progress. $ARGUMENTS is an optional work item filename. if omitted, first look for an in-progress item to resume, then fall back to the next ready item (oldest by date).

/spec-implement
/spec-implement 2026-03-08-implement-config-loader.md

follow these steps:

setup

  1. select the work item. if a filename is provided, locate it in specs/work/active/. if not provided, glob for all files in specs/work/active/, read their frontmatter, and:

    • if any items have status: in-progress, select the oldest one (this is a resume)
    • otherwise, select the oldest item with status: ready
    • if no ready or in-progress items exist, inform the user
  2. read the work item. understand the summary, tasks, and any existing log entries.

  3. read the feature context. using the feature field from the frontmatter, read:

    • specs/features/<feature>/proposal.md — for the high-level intent
    • specs/features/<feature>/spec.md — for the technical details and source paths
  4. read the current code. using the source paths from the spec, read existing code to understand what is already in place.

  5. mark the work item as in-progress. update the frontmatter status to in-progress (if resuming, it will already be set).

  6. if resuming, review previous progress. read the existing log entries and check which tasks are already marked [x]. understand what was previously done and pick up from the first incomplete task.

  7. create a task list for progress tracking. using the work item's tasks checklist, create a corresponding task for each item using TaskCreate. if resuming, mark already-completed tasks as done. this gives the user real-time visibility and preserves your progress if context compresses.

Read the full file on GitHub · 97 lines

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 · 97 lines · 27 tokens per session scan A da196f461e1e

Subscribe to this mod's changes

spec-implement is a skill published in the GitHub repository schmidthole/serf (2 stars, last pushed 5mo ago), licensed BSD-3-Clause. It adds 27 tokens to every session and 1,395 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.

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