section-writer

section-writer is an agent for Claude Code from piercelamb/deep-plan. It costs 26 tokens per session (268 once invoked), scanned A, original, MIT.

An agent that writes a complete implementation section in Markdown for a larger planning workflow. It reads a supplied prompt and its referenced context files, then outputs only that section.

In plain words
What is it for?
Use it within a deep-plan workflow to generate isolated sections for coding work, with test-first guidance and references to related sections.
Why use it?
It gives each planned section enough background, tests, implementation detail, file locations, and dependencies to be understood on its own.

Agent for Claude Code

Written for Claude Code: SubagentStop hook event. Also seen: model in frontmatter.

Part of the deep-plan plugin — 1 skill, 2 agents, 2 hooks shipped together

Good fit Use it within a deep-plan workflow to generate isolated sections for coding work, with test-first guidance and references to related sections.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/piercelamb/deep-plan/section-writer
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.

Clone the repo
git clone --depth 1 https://github.com/piercelamb/deep-plan

Made for: Claude Code.

Or install deep-plan, the plugin that ships this one along with the rest of its 1 skill, 2 agents, 2 hooks.

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 section-writer

README.md
[![agentmods](https://agentmods.dev/badge/agents/piercelamb/deep-plan/section-writer/github.svg)](https://agentmods.dev/agents/piercelamb/deep-plan/section-writer)
Your own site
<a href="https://agentmods.dev/agents/piercelamb/deep-plan/section-writer"><img src="https://agentmods.dev/badge/agents/piercelamb/deep-plan/section-writer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for section-writer

Your own site · 80×15
<a href="https://agentmods.dev/agents/piercelamb/deep-plan/section-writer"><img src="https://agentmods.dev/badge/agents/piercelamb/deep-plan/section-writer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 26 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 268 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.
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 $0.00268
Opus 5.5 $0.00010 $0.00107
Sonnet 5.5 $0.00005 $0.00054
Haiku 4.5 $0.00003 $0.00027

Measured 2mo ago against content hash e8de5f448cb2, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

section-writer 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 2mo 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.

agents/section-writer.md · 32 lines

What it actually says

You are a section-writer agent for the deep-plan workflow. Your job is to generate complete, self-contained implementation section content.

Instructions

  1. Read the prompt file specified in the user message (format: "Read /path/to/prompt.md and execute...")
  2. Read all context files referenced in the prompt
  3. Generate the section content as specified
  4. Output ONLY the raw markdown content for the section

Important: A SubagentStop hook automatically extracts your output and writes it to the correct file location. You do NOT need to output JSON or specify the filename - just output the markdown content directly.

Section Content Requirements

Each section must be implementable in isolation:

  • Tests FIRST (extracted from claude-plan-tdd.md).
  • Implementation details (extracted from claude-plan.md)
  • All necessary background context
  • File paths for code to create/modify
  • Dependencies on other sections (reference only, don't duplicate)
  • CRITICAL Remember that tests and code should only be fully specified if absolutely necessary. Stub definitions and docstrings are fine.
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. 2mo ago First seen · 32 lines · 26 tokens per session scan A e8de5f448cb2

Subscribe to this mod's changes

section-writer is an agent published in the GitHub repository piercelamb/deep-plan (101 stars, last pushed 4mo ago), licensed MIT. It adds 26 tokens to every session and 268 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-30.

Related

Other agents, from other repositories

spec-debugger

Fixes issues when Tester or Reviewer reject an implementation. Fresh perspective on problems the Implementer couldn't solve.

Habib0x0/spec-driven-plugin · 25 tokens

spec-scanner

Scans a codebase using LLM-driven heuristics to detect framework, patterns, entities, and registration points. Produces a persistent project profile that other agents read for wiring-aware implementation.

Habib0x0/spec-driven-plugin · 41 tokens

spec-acceptor

Performs user acceptance testing by mapping completed tasks back to requirements and verifying traceability, non-functional requirements, and overall completeness. Produces a UAT report with pass/fail per acceptance criterion and a formal sign-off recommendation. Does NOT re-run functional tests (the spec-tester…

Habib0x0/spec-driven-plugin · 251 tokens

spec-documenter

Generates user-facing documentation from spec files and implemented code. Produces API references, user guides, and architecture decision records. Context: Feature implementation is complete and user needs documentation. user: "/spec-docs" assistant: "I'll generate documentation from the spec and implementation." The…

Habib0x0/spec-driven-plugin · 100 tokens

spec-validator

Use this agent when you need to validate a spec for completeness, consistency, and implementation readiness. Examples: Context: User has finished creating a spec and wants to verify it's ready for implementation. user: "I've finished the spec for user-authentication. Can you validate it?" assistant: "I'll use the…

Habib0x0/spec-driven-plugin · 275 tokens

spec-consultant

Domain expert consultant that provides focused analysis on a specific topic during brainstorming. This is a parameterized agent — the spawning command passes the expert role, domain expertise, discussion context, and specific question via the prompt. Returns structured analysis to the Lead. Context: During…

Habib0x0/spec-driven-plugin · 228 tokens