forge-speccer

forge-speccer is an agent for Claude Code from LucasDuys/forge. It costs 31 tokens per session (1,123 once invoked), scanned A, original, MIT.

A specification-writing agent that turns brainstorming results into a structured software specification. The specification contains numbered requirements and testable acceptance criteria.

In plain words
What is it for?
It is for creating Forge specification files with an overview, ordered requirements, checkboxes describing observable results, project metadata, and linked repositories.
Why use it?
It converts an idea and discussion into a concrete plan that developers can verify, including both expected behavior and error cases.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the forge plugin — 10 skills, 13 commands, 9 agents, 3 hooks shipped together

Good fit It is for creating Forge specification files with an overview, ordered requirements, checkboxes describing observable results, project metadata, and linked repositories.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/lucasduys/forge/forge-speccer
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/LucasDuys/forge

Made for: Claude Code.

Or install forge, the plugin that ships this one along with the rest of its 10 skills, 13 commands, 9 agents, 3 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 forge-speccer

README.md
[![agentmods](https://agentmods.dev/badge/agents/lucasduys/forge/forge-speccer/github.svg)](https://agentmods.dev/agents/lucasduys/forge/forge-speccer)
Your own site
<a href="https://agentmods.dev/agents/lucasduys/forge/forge-speccer"><img src="https://agentmods.dev/badge/agents/lucasduys/forge/forge-speccer/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 forge-speccer

Your own site · 80×15
<a href="https://agentmods.dev/agents/lucasduys/forge/forge-speccer"><img src="https://agentmods.dev/badge/agents/lucasduys/forge/forge-speccer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 31 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,123 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 $0.00031 $0.01123
Opus 5.5 $0.00012 $0.00449
Sonnet 5.5 $0.00006 $0.00225
Haiku 4.5 $0.00003 $0.00112

Measured 1mo ago against content hash c2a9028a70b5, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

forge-speccer 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 1mo 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/forge-speccer.md · 108 lines

How it starts

The opening of the file, as written. The whole thing — 108 lines — stays where its author put it; the contents beside it link to each section on GitHub.

forge-speccer Agent

You are the Forge specification writer. Your role is to take the output of a brainstorming session (user's topic, Q&A answers, chosen approach) and produce a well-structured specification file.

Your Responsibilities

  1. Write specs in .forge/specs/spec-{domain}.md matching the Forge spec template format
  2. Number requirements sequentially as R001, R002, R003...
  3. Write testable acceptance criteria as checkbox items under each requirement
  4. Cover both happy paths and error cases for every requirement
  5. Organize requirements logically — data model before endpoints, endpoints before UI, core before optional

Output Format

Every spec you write MUST follow this structure:

---
domain: {domain-slug}
status: approved
created: {YYYY-MM-DD}
complexity: {simple|medium|complex}
linked_repos: [{repos if multi-repo}]
---

# {Domain Title} Spec

## Overview
{What this domain does, why it exists, which approach was chosen.}

## Requirements

### R001: {Requirement Name}
{Clear description of what must be built.}
**Acceptance Criteria:**
- [ ] {Specific, observable, testable criterion}
- [ ] {Another criterion}

### R002: {Next Requirement}
...

## Future Considerations
{Features discussed but deferred from v1. Listed here so they are not forgotten but are explicitly out of scope.}

Rules for Acceptance Criteria

  • Be specific. Bad: "Login should work." Good: "POST /auth/login with valid {email, password} returns 200 with {access_token, refresh_token, expires_in}."
  • Be observable. Each criterion must be verifiable by running the code, calling an API, or checking a UI behavior.
  • Include error cases. If R001 is "User Registration", criteria must cover both success (201) and failure (409 duplicate, 400 validation errors).
  • Use concrete values. Not "returns appropriate status code" but "returns 409 Conflict if email already exists."
  • One assertion per checkbox. Split compound criteria into separate checkboxes.

Read the full file on GitHub · 108 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. 1mo ago First seen · 108 lines · 31 tokens per session scan A c2a9028a70b5

Subscribe to this mod's changes

forge-speccer is an agent published in the GitHub repository LucasDuys/forge (56 stars, last pushed 3mo ago), licensed MIT. It adds 31 tokens to every session and 1,123 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

documentation-manager

Expert documentation specialist. Proactively updates documentation when code changes are made, ensures README accuracy, and maintains comprehensive technical documentation. Be sure to give this subagent information on the files that were changed so it knows where to look to document changes. Always call this agent…

berekvolgyipeter/dotclaude · 61 tokens

thermo-nuclear-code-quality-review-subagent

Thermo-nuclear code quality audit (maintainability, structure, 1k-line rule, spaghetti, code-judo). Invoked through the Agent tool after a parent gathers diff and file contents. Loads rubric from the thermo-nuclear-code-quality-review skill in this plugin.

michael-denyer/pstack-claude · 68 tokens

deep-research-patcher

Applies critic findings to a nav-deep-research draft as surgical Edit hunks and records a patch log. Tool-locked so it cannot regenerate the report. Spawned once at step 5 by the nav-deep-research skill.

qf-studio/navigator · 55 tokens

cross-repo-prd-writer

Generates cross-repo PRD documents for missing capabilities based on discovery results.

closedloop-ai/claude-plugins · 24 tokens

verification-subagent

Verifies if a task from the implementation plan has been completed by checking source files.

closedloop-ai/claude-plugins · 21 tokens

vibe-change-worker

The one persistent implementation writer for a vibe session. Keeps the same context, worktree and branch while planning, implementing all frontend/backend/prototype/component work, fixing reviewed issues, repairing existing tests its change broke and listing the missing tests for engineering at handoff; it writes…

closedloop-ai/claude-plugins · 102 tokens