spec-driven-development-template copilot-instructions.md

A template for specification-driven development, where a project’s approved written requirements and plan come before its code.

In plain words
What is it for?
Planning and building projects with GitHub Spec Kit workflows, an optional specification sidecar, and MCP support.
Why use it?
It prevents implementation from starting before the intended behavior is agreed and documented.

Instructions file for GitHub Copilot

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 instructions/juanklagos/spec-driven-development-template/copilot-instructions
Clone the repo
git clone --depth 1 https://github.com/juanklagos/spec-driven-development-template

Made for: GitHub Copilot.

Per session 493 This file is loaded in full into every session.
When invoked 493 The same file — it is already loaded in full.
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 $0.00493 $0.00493
Opus 5 $0.00246 $0.00246
Sonnet 5 $0.00099 $0.00099
Haiku 4.5 $0.00049 $0.00049

Measured 2d ago against content hash 32dff9310abd, 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-development-template copilot-instructions.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 2d 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.

.github/copilot-instructions.md · 33 lines

What it actually says

GitHub Copilot Instructions - SDD Template

Canonical source:

  • template-context/core-instructions/AGENT_OPERATING_SYSTEM.md
  • sdd.policy.yaml

Hard stop:

  • No code before approved spec and consistent plan.
  • No hay código sin spec aprobada y plan consistente.

Execution workspace:

  • Inside THIS template repository, put runnable code under www/<project-name>/.
  • For a project that already exists somewhere else — the common case — install the compact spec/ sidecar in it and leave the code where it is. That is the recommended default workspace for real work.
  • Dentro de ESTA plantilla, el código ejecutable va en www/<nombre-proyecto>/.
  • Para un proyecto que ya existe en otro sitio —el caso normal— instala el sidecar compacto spec/ y deja el código donde está. Ese es el espacio de trabajo recomendado por defecto para el trabajo real.
  • The user may choose another target path.
  • If the target project lives inside this template, keep it under www/.
  • For real external projects, install the compact spec/ sidecar and keep code in the project root.
  • Para proyectos reales externos, instala el sidecar compacto spec/ y mantén el código en la raíz del proyecto.

Required behavior:

  1. Treat this repository as a starter template, not a product backlog.
  2. Read AI_START_HERE.md, idea/IDEA_GENERAL.md, specs/INDEX.md first.
  3. Work from one active specification.
  4. If gate is not met, refine docs (spec, plan, tasks, history, bitacora) only.
  5. Keep traceability in history.md, specs/INDEX.md, and bitacora/.
  6. Record a decision in bitacora/decisiones/YYYY-MM-DD-<slug>.md when it chose between real alternatives, will be expensive to reverse, or a future reader would ask "why is it like this?". Include a "when to revisit" section, source every rationale (commit, file:line, spec history, CHANGELOG, idea/), and never invent one.

Validation commands:

  • ./scripts/validate-sdd.sh . --strict
  • ./scripts/check-sdd-policy.sh .
  • ./scripts/check-sdd-gate.sh .
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. 2d ago First seen · 33 lines · 493 tokens per session scan A 32dff9310abd

Subscribe to this mod's changes

spec-driven-development-template copilot-instructions.md is an instructions file published in the GitHub repository juanklagos/spec-driven-development-template (15 stars, last pushed 2d ago), licensed MIT. It adds 493 tokens to every session, about $0.0025 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.