sdd-mcp: Instructions file for Codex

AGENTS.md

sdd-mcp AGENTS.md is an instructions file for Codex, OpenCode from yi-john-huang/sdd-mcp. It costs 416 tokens per session, scanned A, original, MIT.

Project instructions for sdd-mcp, a tool that guides coding work through approved requirements, design, task, and implementation stages.

In plain words
What is it for?
Choosing the right workflow for small or formal changes, finding specifications and tests, and routing work to the appropriate model.
Why use it?
They prevent work from skipping review or approval stages and explain where project files belong.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions Claude Code; mentions Codex.

This is yi-john-huang/sdd-mcp's own configuration. It tells Codex and OpenCode how to work on sdd-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything sdd-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to yi-john-huang/sdd-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/yi-john-huang/sdd-mcp/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/yi-john-huang/sdd-mcp

Made for: Codex, OpenCode.

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.

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README.md
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Your own site
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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 sdd-mcp AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/yi-john-huang/sdd-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/yi-john-huang/sdd-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 416 This file is loaded in full into every session.
When invoked 416 The same file — it is already loaded in full.
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 $0.00416 $0.00416
Opus 5 $0.00208 $0.00208
Sonnet 5 $0.00083 $0.00083
Haiku 4.5 $0.00042 $0.00042

Measured 9d ago against content hash 7952efe723be, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

sdd-mcp AGENTS.md 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 9d 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.md · 27 lines

What it actually says

SDD-MCP Project Guidance

This repository develops sdd-mcp-server, a spec-driven workflow for Claude Code, Codex, and Oh My Pi (OMP).

Workflow

  • Install the chosen host target, reload it, and accept the host's project trust prompt before starting.
  • Small fixes: invoke /skill:simple-task.
  • Formal work: invoke /skill:sdd-requirements <feature-name>, then /skill:sdd-design, /skill:sdd-tasks, and /skill:sdd-implement after each explicit approval.
  • Never cross an unapproved phase. When configured, test-case review is a separate explicit decision before tasks approval.
  • Skills automatically restore durable status and approved compact context. Do not ask users to operate MCP tools or paste workflow JSON.

Repository layout

  • Canonical components: skills/, agents/, rules/, contexts/, hooks/, steering/, templates/.
  • Implementation: src/; focused tests: src/__tests__/.
  • Specifications and project steering: .spec/specs/ and .spec/steering/.
  • Generated native targets are installed under .claude/, .agents/ + .codex/, or .omp/; do not hand-edit generated files.

Model routing

Planning, architecture, review, and security run inline on Sol/medium by default in OMP; project Sol/xhigh advisors are explicit opt-in. Claude uses current-turn Opus/Sonnet routing, while Codex may use one configured Sol/xhigh custom advisor.

Run implementation, TDD, simple tasks, and commits in the parent unless at least two genuinely independent implementation slices can run concurrently. If an advisor is explicitly invoked, allow one specialist without nesting; on model, auth, or agent failure, record one fallback and continue in the parent without retrying.

See docs/MODEL-ROUTING.md for route details and docs/WORKFLOW.md for the complete workflow.

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. 9d ago First seen · 27 lines · 416 tokens per session scan A 7952efe723be

Subscribe to this mod's changes

sdd-mcp AGENTS.md is an instructions file published in the GitHub repository yi-john-huang/sdd-mcp (51 stars, last pushed 1mo ago), licensed MIT. It adds 416 tokens to every session, about $0.0021 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 2026-08-30.

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