---
name: external-resource-context
description: Captures access methods for resources outside the repository (design source, design system, API schema, IaC source, secret store) into a deterministic location so downstream work can reach them. Use when capturing or updating those access methods, or when the user mentions design source, design system, API schema, IaC source, secret store, or canonical source.
---

# External Resource Context

## Purpose

AI agents understand the codebase but not the external resources surrounding it. This skill captures, in a deterministic location, the **access methods** to resources outside the repository so downstream work (design, planning, implementation, review) can reach them without re-asking the user.

Resources covered: design origin (where the canonical visual specification lives), design system (component library and tokens), guidelines (usage docs, accessibility rules), visual verification environment (how to confirm rendering), database schema source, migration history, secret store location, API schema source (OpenAPI / proto / GraphQL SDL), mock environment, IaC source, environment configuration.

## Scope Boundaries

**In scope**: hearing protocol, storage location, single-source-of-truth ownership rule, reference protocol for downstream consumers.

**Out of scope**: enforcing that captured resources are correct or current — verification belongs to the agent that consumes the resource. Generating the resources themselves (e.g., creating a DESIGN.md from scratch).

## Storage Locations (Two-Tier)

| Tier | Location | Holds | Update Frequency |
|------|----------|-------|------------------|
| Project | `docs/project-context/external-resources.md` | Environment-stable facts: which resources exist for this project and how to access them (URL, MCP name, file path, command) | Rare — only when the project's environment changes |
| Feature | `## External Resources Used` section inside the relevant UI Spec or Design Doc | The subset of project-tier resources actually used by this feature, plus feature-specific identifiers (e.g., a specific node id within the design tool, a specific endpoint path) | Per feature |

### Single Source of Truth Rule

The project tier owns environment facts. Feature-tier sections list only feature-specific identifiers (node id within the design source, specific endpoint path within the API, specific IaC module name) and reference project-tier entries by label; URLs, MCP names, and access commands remain in the project-tier file. When the environment changes, only the project-tier file is updated.

Example feature-tier entry uses the table format defined in `references/template.md`: a row with the project-tier label in the first column and the feature-specific identifier in the second column.

## Reference Protocol (For Downstream Consumers)

Consuming a recorded resource takes three reads and needs no part of this skill:

1. Read `docs/project-context/external-resources.md` (if present) to learn what is available and how to access it.
2. Read the target UI Spec or Design Doc's `## External Resources Used` section for feature-specific identifiers.
3. Use the access method declared in the project tier (e.g., the named MCP, the URL, the file path) to fetch the actual resource content.

A consumer that only reads these records executes the three steps directly. Load this skill when capturing or updating the records, which requires AskUserQuestion and therefore the session that can ask the user.

## Capturing and Updating Records

Follow [references/hearing.md](references/hearing.md) for the hearing conditions, domain routing, two-phase hearing, storage protocol, and quality checklist.

## Output Format

The project-tier file follows the structure in [references/template.md](references/template.md). The project-tier file's heading levels and section names are fixed so downstream agents can locate sections deterministically.

For feature-tier sections inside UI Spec or Design Doc, the heading text "External Resources Used" is fixed; the heading level matches the parent document's natural structure (h2 in UI Spec where it is a sibling of other top-level sections, h3 in Design Doc where it sits under Background and Context).

## References

- [references/hearing.md](references/hearing.md) — Hearing conditions, domain routing, storage protocol, quality checklist
- [references/frontend.md](references/frontend.md) — Frontend domain axes
- [references/backend.md](references/backend.md) — Backend domain axes
- [references/api.md](references/api.md) — API contract domain axes
- [references/infra.md](references/infra.md) — Infrastructure domain axes
- [references/template.md](references/template.md) — Project-tier and feature-tier structure templates