Borrowing it
Nothing to install: this file belongs to jaccoklouwer/ast-indexer. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/jaccoklouwer/ast-indexer/main/.github/copilot-instructions.mdgit clone --depth 1 https://github.com/jaccoklouwer/ast-indexerWrote 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.
[](https://agentmods.dev/instructions/jaccoklouwer/ast-indexer/copilot-instructions)<a href="https://agentmods.dev/instructions/jaccoklouwer/ast-indexer/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/jaccoklouwer/ast-indexer/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.
<a href="https://agentmods.dev/instructions/jaccoklouwer/ast-indexer/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/jaccoklouwer/ast-indexer/copilot-instructions.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.01579 | $0.01579 |
| Opus 5 | $0.00790 | $0.00790 |
| Sonnet 5 | $0.00316 | $0.00316 |
| Haiku 4.5 | $0.00158 | $0.00158 |
Grade A, and why
ast-indexer 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 8d 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.
How it starts
The opening of the file, as written. The whole thing — 145 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AST-Indexer MCP Server - AI Coding Instructions
Project Overview
This is a Model Context Protocol (MCP) server that indexes Git repositories using Abstract Syntax Tree parsing. It extracts functions, classes, imports, variables, and SQL schema objects from JS/TS, C#, and SQL files, making them searchable through MCP tools.
Architecture
Parser Dispatch Pattern
src/parser.ts acts as the entry point and dispatcher - routes to language-specific parsers based on file extension:
.js/.jsx/.ts/.tsx→parseJavaScriptFile()(uses TypeScript Compiler API).cs→ src/csharp-parser.ts (uses Tree-sitter).sql→ src/sql-parser.ts (uses node-sql-parser)
All parsers return the same FileIndex schema structure - critical for consistency.
Core Components
- src/indexer.ts:
RepositoryIndexerclass manages repo scanning, caching (in-memory Map), and search operations - src/schemas.ts: Single source of truth for all data structures using Zod validation
- src/index.ts: MCP server setup with tool definitions and request handlers
Data Flow
- MCP client calls
index_repository→ RepositoryIndexer scans directory - For each file: dispatcher routes to language parser → returns FileIndex
- All FileIndex objects cached in Map keyed by repositoryPath
- Search tools query cached index using string matching; tools accept
caseInsensitiveto control matching
Language-Specific Patterns
JavaScript/TypeScript (TypeScript Compiler API)
- Uses
ts.createSourceFile()with ScriptKind determined by extension (JS/JSX/TS/TSX) - Recursive tree traversal using
ts.forEachChild()pattern - Distinguishes function types:
function,async,arrow(for arrow functions assigned to variables) - Extracts return types from TypeScript type annotations when available
- Full support for JSX/TSX via ScriptKind.JSX/TSX
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.
- 8d ago First seen · 145 lines · 1,579 tokens per session scan A 08d9df056891
ast-indexer copilot-instructions.md is an instructions file published in the GitHub repository jaccoklouwer/ast-indexer (0 stars, last pushed 2d ago), licensed ISC. It adds 1,579 tokens to every session, about $0.0079 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.
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vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
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langchain AGENTS.md
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deepseek-harness AGENTS.md
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