spec-driven-dev

A set of rules for Spec-Driven Development, a workflow where a written specification guides feature and architecture changes. It provides templates for specifications and architecture decision records.

In plain words
What is it for?
It is for adding features, creating API endpoints, or changing architecture while recording the intended behavior and important design decisions.
Why use it?
It gives development work a documented starting point before code is changed. This helps keep new features, endpoints, and architecture decisions consistent with the project plan.

Cursor rule

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 rules/ziolson/ai-context-hub/spec-driven-dev
Clone the repo
git clone --depth 1 https://github.com/Ziolson/ai-context-hub
Per session 20 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 100 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 $0.00020 $0.00100
Opus 5 $0.00010 $0.00050
Sonnet 5 $0.00004 $0.00020
Haiku 4.5 $0.00002 $0.00010

Measured yesterday against content hash 991480ad3de9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

spec-driven-dev 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 yesterday.

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.

adapters/cursor/rules/spec-driven-dev.mdc · 16 lines

What it actually says

Follow the Spec-Driven Development workflow defined in @docs/workflows/spec-driven-development.md

Use the following templates:

  • @docs/templates/spec-template.md — Specification template
  • @docs/templates/adr-template.md — ADR template (when architectural decisions are needed)

Also apply the global rules from @rules/global-rules.md

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. yesterday First seen · 16 lines · 20 tokens per session scan A 991480ad3de9

Subscribe to this mod's changes

spec-driven-dev is a cursor rule published in the GitHub repository Ziolson/ai-context-hub (2 stars, last pushed 22d ago), licensed MIT. It adds 20 tokens to every session and 100 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.