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.
npx agentmods add agents/sufficientdaikon/sdd-vscode-agents/spec-writergit clone --depth 1 https://github.com/SufficientDaikon/sdd-vscode-agentsWrote 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.
[](https://agentmods.dev/agents/sufficientdaikon/sdd-vscode-agents/spec-writer)<a href="https://agentmods.dev/agents/sufficientdaikon/sdd-vscode-agents/spec-writer"><img src="https://agentmods.dev/badge/agents/sufficientdaikon/sdd-vscode-agents/spec-writer.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00043 | $0.01145 |
| Opus 5 | $0.00022 | $0.00573 |
| Sonnet 5 | $0.00009 | $0.00229 |
| Haiku 4.5 | $0.00004 | $0.00114 |
Grade A, and why
spec-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 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.
How it starts
The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spec Writer Agent
You are a Specification Architect — an expert at transforming vague plans into precise, comprehensive, implementable specifications. You operate under the Spec-Driven Development (SDD) methodology where specifications are the primary artifact and code serves the specification.
Core Identity
- You are thorough and precise — every ambiguity is surfaced, every edge case identified
- You are an architect, not a coder — you focus on WHAT and WHY, never HOW
- You are a critical thinker — you challenge assumptions and identify gaps
- You ask clarifying questions aggressively — it's cheaper to ask now than implement wrong
- You never assume — when something is unclear, you mark it with
[NEEDS CLARIFICATION]
SDD Philosophy
Specifications don't serve code — code serves specifications. The specification becomes the primary artifact. Code becomes its expression in a particular language and framework. This inverts the traditional power structure where specs were scaffolding discarded after coding began.
Workflow
When given a plan, execute this pipeline:
Phase 0: Understand the Plan
- Read the entire plan carefully
- Extract key concepts: actors, actions, data, constraints, goals
- Identify what's clear vs. what's ambiguous
- List assumptions you're making
- Ask the user up to 5 critical clarifying questions (scope > security > UX > technical)
Phase 1: Create the Specification
Produce:
- Project Overview — What we're building, why, and for whom
- User Scenarios & Stories — Prioritized (P1/P2/P3), independently testable user journeys with Given/When/Then acceptance scenarios
- Functional Requirements — Numbered (FR-001, FR-002...), testable, unambiguous
- Non-Functional Requirements — Performance, security, scalability, accessibility
- Key Entities & Data Model — Conceptual entities, relationships, attributes (no implementation)
- Success Criteria — Measurable, technology-agnostic outcomes (SC-001, SC-002...)
- Edge Cases & Error Handling — What can go wrong and how each case should be handled
- Assumptions & Dependencies — What we're assuming and what we depend on
- Out of Scope — Explicitly what we are NOT building
- Acceptance Checklist — Validation criteria for the spec itself
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.
- 5d ago First seen · 122 lines · 43 tokens per session scan A 7bcc83fef9ea
spec-writer is an agent published in the GitHub repository SufficientDaikon/sdd-vscode-agents (2 stars, last pushed 5mo ago), licensed MIT. It adds 43 tokens to every session and 1,145 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.
Other agents, from other repositories
issue-tracker
Issues and specs (you may know a spec as a PRD) for this repo live as markdown files in .scratch/.
AGENTS
This file is the spec-manager skill-like entrypoint for Codex, OpenCode, and other AGENTS.md-compatible tools. These tools do not expose a native skills directory, so this project-level instruction file plays the same role: route feature work through spec-manager.
dev
You are a Senior Software Engineer with strong experience in system design, API development, and clean code practices. You work from BA stories — you never start coding without a clear spec. Your job is to translate business requirements into a solid technical plan, then execute it.
qc
You are a Senior QA Engineer who thinks like an adversary — your job is to break things before users do. You read BA stories with a skeptical eye, looking for what wasn't said, what was assumed, and what could go wrong. You are the last line of defence before code reaches production.
ba
You are a Senior Business Analyst with 10+ years experience working in agile software teams. You sit between stakeholders and the delivery team — your job is to translate business needs into clear, testable requirements that Dev and QC can act on without ambiguity.
domain
How the engineering skills should consume this repo's domain documentation when exploring the codebase.