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.
npx agentmods add instructions/crossplane-contrib/crossplane-diff/claude-mdgit clone --depth 1 https://github.com/crossplane-contrib/crossplane-diffWhat 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 | $0.06018 | $0.06018 |
| Opus 5 | $0.03009 | $0.03009 |
| Sonnet 5 | $0.01204 | $0.01204 |
| Haiku 4.5 | $0.00602 | $0.00602 |
Grade A, and why
crossplane-diff CLAUDE.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 3d 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 — 482 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Development Commands
Building and Testing
# Build the binary for your platform
earthly +build
# Run unit and integration tests (fast, ~7s)
# Direct go test - fastest, immediate output
cd cmd/diff
go test ./...
# Via Earthly (ensures consistent environment, caches dependencies)
earthly +go-test
# Run a specific test
go test ./cmd/diff/diffprocessor -run TestCachedFunctionProvider -v
# Run a single test file
go test ./cmd/diff/diffprocessor/diff_processor_test.go -v
# Check test coverage
go test -cover ./cmd/diff/diffprocessor/... -coverprofile=/tmp/coverage.out
go tool cover -func=/tmp/coverage.out
# Pre-PR checks: linting, tests, generation (requires long timeout, can take several minutes)
earthly -P +reviewable
# Fetch Crossplane cluster CRDs (required after Crossplane API changes or for integration tests)
earthly +fetch-crossplane-cluster --CROSSPLANE_IMAGE_TAG=main
# Tidy go modules
earthly +generate
Earthly Output Notes:
- By default, Earthly buffers stdout and stderr separately, which can cause interleaved output
- Use
2>&1to merge streams for chronological output:earthly +go-test 2>&1 | tee output.log
End-to-End Tests
E2E tests run against real kind clusters with Crossplane installed. They can take several minutes to complete.
# Full E2E matrix against multiple Crossplane versions (slow, runs serially)
earthly -P +e2e-matrix
# Single E2E test against specific Crossplane version
earthly +e2e --CROSSPLANE_IMAGE_TAG=main
# Run specific E2E test with verbose logging
earthly -P +e2e --FLAGS="-v=4 -test.run ^TestCompositionDiff"
# Debug E2E: stop on first failure and preserve kind cluster
earthly -i -P +e2e --FLAGS="-test.failfast -fail-fast -destroy-kind-cluster=false"
# Run E2E tests directly (without Earthly wrapper for easier debugging)
go test -c -o e2e ./test/e2e
./e2e -v=4 -test.v -test.failfast -destroy-kind-cluster=false -test.run ^TestSpecificTest
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.
- 3d ago First seen · 482 lines · 6,018 tokens per session scan A 6b71545eaa38
crossplane-diff CLAUDE.md is an instructions file published in the GitHub repository crossplane-contrib/crossplane-diff (42 stars, last pushed 3d ago), licensed Apache-2.0. It adds 6,018 tokens to every session, about $0.0301 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.
Other instructions, from other repositories
no-mistakes AGENTS.md
AGENTS.md instructions for kunchenguid/no-mistakes, covering agents.md and maintaining this file.
trpc-agent-go AGENTS.md
AGENTS.md instructions for trpc-group/trpc-agent-go, covering agents.md, project overview, engineering principles, go design conventions and implementation workflow.
azure-sdk-for-go go-code.instructions.md
Instructions for Azure/azure-sdk-for-go: All code should follow the guidelines from the Azure Go SDK Guidelines. This document is a summary of the most important guidelines to follow when contributing to the Azure Go SDK.
goai AGENTS.md
Instructions for zendev-sh/goai, covering agents.md - goai, commands, architecture, key rules and adding providers.
unraid-management-agent copilot-instructions.md
Instructions for ruaan-deysel/unraid-management-agent, covering copilot instructions, copilot workflow, path-specific instructions, reusable prompts and quick commands.
coral CLAUDE.md
Instructions for cdknorow/coral, covering claude.md - coral go, mission, testing, go unit tests and legacy parity tools (historical reference).