What is agent-atlas copilot-instructions.md?

Repository guidance for Agent Atlas, an ASP.NET Core application that catalogs internal APIs as tools that people and AI agents can discover and use. It also describes the service layout, execution system, and developer interface.

Use it when developing or reviewing Agent Atlas, especially work involving its API catalog, MCP server, JSON plan execution, React interface, or .NET Aspire setup.

It gives coding agents the project context they need to navigate the repository and follow its intended architecture. This reduces confusion about where features belong and how the parts fit together.

How rebeccapowell/agent-atlas configures GitHub Copilot

Reuse

Borrowing it

Nothing to install: this file belongs to rebeccapowell/agent-atlas. 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/rebeccapowell/agent-atlas/main/.github/copilot-instructions.md

Clone the repo

git clone --depth 1 https://github.com/rebeccapowell/agent-atlas

Made for: GitHub Copilot.

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/rebeccapowell/agent-atlas/copilot-instructions/github.svg)](https://agentmods.dev/instructions/rebeccapowell/agent-atlas/copilot-instructions)

Your own site

<a href="https://agentmods.dev/instructions/rebeccapowell/agent-atlas/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/rebeccapowell/agent-atlas/copilot-instructions/github.svg" alt="Measured on agentmods" height="20"></a>

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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/rebeccapowell/agent-atlas/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/rebeccapowell/agent-atlas/copilot-instructions.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 5,080 This file is loaded in full into every session.

When invoked 5,080 The same file — it is already loaded in full.

Security scan A 1 finding. 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.

Model	Per session	Once invoked
Fable 5.1	$0.05080	$0.05080
Opus 5.5	$0.02032	$0.02032
Sonnet 5.5	$0.01016	$0.01016
Haiku 4.5	$0.00508	$0.00508

Measured 2mo ago against content hash 2b6da4451f0d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

agent-atlas copilot-instructions.md scanned grade A with 1 finding 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 2mo 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -sf http://localhost:5063/healthz # should return "Healthy"

.github/copilot-instructions.md · 410 lines

How it starts

The opening of the file, as written. The whole thing — 410 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Copilot Instructions for Agent Atlas

Project Overview

Agent Atlas is an enterprise MCP (Model Context Protocol) gateway built with ASP.NET Core 10 and .NET Aspire. It turns a messy internal API estate into a governed, searchable catalog of MCP tools that both humans and AI agents can discover and invoke safely.

Catalog: Reads OpenAPI specs from a GitOps data-plane repository. Teams annotate operations with x-mcp vendor extensions to mark them as agent tools.
MCP Server: Exposes three MCP tools — SearchTools, DescribeTool, ExecutePlan — via Streamable HTTP transport at /mcp.
Execution Engine: Interprets a JSON plan DSL (call, foreach, if, return steps) and proxies requests to downstream APIs, forwarding the caller's JWT.
React UI: A read-only capability map for developers and operators (served from wwwroot).

Repository Layout

src/
  Atlas.AppHost/         # .NET Aspire orchestration host (local dev entry point)
  Atlas.Host/            # Main service: MCP server, catalog API, execution engine, React UI
  SampleApi.ToolEnabled/ # Demo API whose operations ARE registered as MCP tools
  SampleApi.NotToolEnabled/ # Demo API intentionally NOT registered as tools
catalog/                 # GitOps data-plane: catalog.yaml, apis/, policies/
docs/                    # Architecture and deployment documentation
helm/                    # Kubernetes / Helm chart

Tech Stack

.NET 10 / ASP.NET Core 10
.NET Aspire 13.x (orchestration, service discovery)
ModelContextProtocol.AspNetCore 1.0.0 (MCP SDK)
Keycloak (OIDC provider for local dev, via Docker)
React (UI, pre-built into wwwroot)
YamlDotNet (catalog YAML parsing)
Microsoft.OpenApi.Readers (OpenAPI spec loading)

Build and Run

IMPORTANT — trust the HTTPS dev certificate first. Aspire uses a local HTTPS certificate for service-to-service communication via DCP (its internal process manager). If the certificate is not trusted, the DCP handshake times out after 20 seconds and the AppHost fails to start. Always run the three cert commands below once before the first aspire run in any new environment.

Read the full file on GitHub · 410 lines

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.

2mo ago First seen · 410 lines · 5,080 tokens per session scan A 2b6da4451f0d

Subscribe to this mod's changes

agent-atlas copilot-instructions.md is an instructions file published in the GitHub repository rebeccapowell/agent-atlas (2 stars, last pushed 8mo ago), licensed MIT. It adds 5,080 tokens to every session, about $0.0203 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Building agents agents apis docker gitops mcp oss

agent-atlas copilot-instructions.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
agent-atlas copilot-instructions.mdrebeccapowell/agent-atlas	Instructions file	2	8mo ago	MIT	A	5,080	GitHub Copilot
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

agent-atlas: Instructions file for GitHub Copilot