Borrowing it
Nothing to install: this file belongs to a2aproject/a2a-tck. 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/a2aproject/a2a-tck/main/AGENTS.mdgit clone --depth 1 https://github.com/a2aproject/a2a-tckWrote 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/a2aproject/a2a-tck/agents-md)<a href="https://agentmods.dev/instructions/a2aproject/a2a-tck/agents-md"><img src="https://agentmods.dev/badge/instructions/a2aproject/a2a-tck/agents-md/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/a2aproject/a2a-tck/agents-md"><img src="https://agentmods.dev/badge/instructions/a2aproject/a2a-tck/agents-md.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 | $0.01476 | $0.01476 |
| Opus 5.5 | $0.00590 | $0.00590 |
| Sonnet 5.5 | $0.00295 | $0.00295 |
| Haiku 4.5 | $0.00148 | $0.00148 |
Grade A, and why
a2a-tck AGENTS.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.
- **diagnose-failure** (`.agents/skills/diagnose-failure/SKILL.md`): Diagnose a TCK requirement failure and draft a GitHub issue with requirement context, failure details, and a curl reproducer. How it starts
The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Project Overview
A2A Protocol Technology Compatibility Kit (TCK) — a conformance test suite that validates A2A-protocol-compliant agents across three transports: gRPC, JSON-RPC, and HTTP+JSON.
Architecture
tck/ # Main package
requirements/ # Requirement specs and error bindings
transport/ # Implemenation of Transport clients
validators/ # Response validators per transport
reporting/ # Compatibility reporting
tests/
unit/ # Unit tests (no SUT needed)
codegen/ # Tests for the code generator
compatibility/ # Conformance tests (require running SUT)
conftest.py # Fixtures: transport_clients, agent_card, compatibility_collector
markers.py # Pytest marker aliases: grpc, jsonrpc, http_json, must, should, may
core_operations/ # Cross-transport parametrized tests
grpc/ # gRPC-specific tests
jsonrpc/ # JSON-RPC-specific tests
http_json/ # HTTP+JSON-specific tests
scenarios/ # Gherkin .feature files defining SUT behaviors
codegen/ # Code generator: parses scenarios and emits SUT projects
parser.py # Gherkin parser
steps.py # Step text → Trigger/Action resolution
model.py # Data model (Scenario, Trigger, Action)
java_emitter.py # Jinja2-based Java/Quarkus emitter (generates CDI producers)
python_emitter.py # Jinja2-based Python emitter
a2a-java/ # Jinja2 templates for a2a-java CDI producers
a2a-python/ # Jinja2 templates for the a2a-python SUT
sut/
a2a-python/ # Generated Python project (a2a-python SDK)
specification/ # A2A spec files and derived resources (JSON schema, proto stubs)
generated/ # Stubs Generated from a2a.proto
.agents/skills/ # Agent skills (see Skills section below)
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 · 100 lines · 1,476 tokens per session scan A f3c1680aaa37
a2a-tck AGENTS.md is an instructions file published in the GitHub repository a2aproject/a2a-tck (56 stars, last pushed 8d ago), licensed Apache-2.0. It adds 1,476 tokens to every session, about $0.0059 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 2026-08-30.
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