collaborative-spec-builder

collaborative-spec-builder is a command for coding agents from jimmc414/claude-code-plugin-marketplace. It costs 12 tokens per session (848 once invoked), scanned A, original, MIT.

A command that leads an iterative question-and-answer session to define a software specification before implementation. It covers the goal, terminology, inputs, outputs, conditions, rules, state changes, and side effects.

In plain words
What is it for?
Use it before building a feature when requirements are incomplete, especially to clarify accepted data, expected results, limits, and behavior.
Why use it?
It helps turn an unclear request into an agreed description of what the software must do, reducing misunderstandings during coding.

Command

Part of the collaborative-spec-builder plugin — 2 commands shipped together

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/jimmc414/claude-code-plugin-marketplace/collaborative-spec-builder
Clone the repo
git clone --depth 1 https://github.com/jimmc414/claude-code-plugin-marketplace

Or install collaborative-spec-builder, the plugin that ships this one along with the rest of its 2 commands.

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 collaborative-spec-builder

README.md
[![agentmods](https://agentmods.dev/badge/commands/jimmc414/claude-code-plugin-marketplace/collaborative-spec-builder.svg)](https://agentmods.dev/commands/jimmc414/claude-code-plugin-marketplace/collaborative-spec-builder)
Your own site
<a href="https://agentmods.dev/commands/jimmc414/claude-code-plugin-marketplace/collaborative-spec-builder"><img src="https://agentmods.dev/badge/commands/jimmc414/claude-code-plugin-marketplace/collaborative-spec-builder.svg" alt="Measured on agentmods" height="20"></a>
Per session 12 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 848 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 $0.00012 $0.00848
Opus 5 $0.00006 $0.00424
Sonnet 5 $0.00002 $0.00170
Haiku 4.5 $0.00001 $0.00085

Measured 5d ago against content hash 6e0fa1466682, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

collaborative-spec-builder 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 5d 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.

plugins/collaborative-spec-builder/commands/collaborative-spec-builder.md · 119 lines

How it starts

The opening of the file, as written. The whole thing — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Collaborative Specification Builder

You are entering a collaborative specification building session with the user. This is an iterative process to define an unambiguous specification before implementation.

Specification Areas to Cover

Systematically gather information across these areas:

Intent

  • What problem does this solve? Why does it need to exist?
  • What is the broader context? What goals guide decisions?
  • What is explicitly out of scope? How will this be used?

Domain Types / Vocabulary

  • What are the core types involved?
  • What do key terms mean precisely?

Input Contract

  • What inputs are accepted? Types, formats, valid ranges?

Output Contract

  • What is returned? Shape/type of output?

Preconditions

  • What must be true before execution?
  • What is validated vs. assumed?

Postconditions

  • What is guaranteed after successful execution?

Invariants

  • What must remain true throughout execution?

Constraints

  • What rules govern valid behavior? What is prohibited?

State Transitions

  • What states can entities be in? What transitions are legal?

Side Effects

  • What external state is modified? What I/O occurs?

Error Cases

  • What can fail? How should each failure be handled?

Boundary Conditions

  • Empty inputs, nulls, zeros, max values?

Assumptions

  • What is assumed true but not explicitly checked?

Dependencies / Environment (if relevant)

  • Required libraries, services, runtime, configuration?

Non-functional Requirements (if relevant)

  • Performance, memory, scalability expectations?

Security (if relevant)

  • Auth requirements, data sensitivity, threat model?

Concurrency (if relevant)

  • Parallel execution, synchronization, race conditions?

Examples / Acceptance Criteria

  • Concrete input/output pairs? Critical test cases?

Phase 1: Specification Gathering (Iterative Q&A)

Begin by understanding what the user wants to build through iterative questioning:

  1. Use the AskUserQuestion tool to ask clarifying questions
  2. You may ask up to 4 questions per round (this is the tool's limit)
  3. Focus each round on specific specification areas that are unclear or undefined
  4. IMPORTANT: Always include this option in every question round:
    • Label: "Done - specification is complete"
    • Description: "The specification is sufficiently clear, proceed to planning"
  5. After receiving answers, analyze the responses and update your understanding
  6. If the user did NOT select "Done", continue asking follow-up questions
  7. Repeat until the user selects "Done - specification is complete"

Read the full file on GitHub · 119 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. 5d ago First seen · 119 lines · 12 tokens per session scan A 6e0fa1466682

Subscribe to this mod's changes

collaborative-spec-builder is a command published in the GitHub repository jimmc414/claude-code-plugin-marketplace (4 stars, last pushed today), licensed MIT. It adds 12 tokens to every session and 848 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.