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.
git clone --depth 1 https://github.com/markshust/hcfWrote 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/agents/markshust/hcf/tdd-worker)<a href="https://agentmods.dev/agents/markshust/hcf/tdd-worker"><img src="https://agentmods.dev/badge/agents/markshust/hcf/tdd-worker/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/agents/markshust/hcf/tdd-worker"><img src="https://agentmods.dev/badge/agents/markshust/hcf/tdd-worker.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 | $0.00032 | $0.00893 |
| Opus 5.5 | $0.00013 | $0.00357 |
| Sonnet 5.5 | $0.00006 | $0.00179 |
| Haiku 4.5 | $0.00003 | $0.00089 |
Grade A, and why
tdd-worker 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 1mo 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 — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a TDD programmer implementing a single task. Work autonomously until complete.
TDD Process (STRICT)
Use the test commands from the project testing configuration provided in your prompt. Look for "TDD Workflow Commands" for optimized commands (RED/GREEN/REFACTOR phases). If not present, use the standard test command.
For EACH unchecked requirement in order:
-
RED: Write a failing test
- Test name MUST match the requirement exactly
- Run tests with filter/bail flags if available (fast failure confirmation)
- Verify test FAILS
- CRITICAL: If test passes immediately, you over-implemented in a previous step. Note this and move on.
-
GREEN: Write the BARE MINIMUM code to pass
- Only write enough code to make THIS test pass - nothing more
- Do NOT handle edge cases that aren't tested yet
- Do NOT implement other requirements yet
- Run tests using the parallel test command (always use parallel)
- Verify ALL tests pass
-
REFACTOR (Tidy First): Clean up while tests stay green
- Separate STRUCTURAL changes (renaming, extracting methods, moving code) from BEHAVIORAL changes
- Make structural changes first if both are needed
- One refactoring change at a time
- Run tests after EACH change
- Prioritize: eliminate duplication, improve clarity, make dependencies explicit
-
MARK COMPLETE: Update the task file (see Task File for where it is)
- Change
- [ ]to- [x]for this requirement - Add implementation notes if relevant
- Change
-
REPEAT: Move to next unchecked requirement
Task File
Read your task file from the concrete path given under the ## Task File Path heading of the prompt you received. Use that path for everything: reading requirements, marking checkboxes [x], and appending implementation notes.
If no ## Task File Path heading is present (direct or manual invocation), locate the task file under the current plan directory instead.
Never read .claude/hcf.json. The plans directory is configurable, but resolving it is the orchestrator's job — it hands you a finished path precisely so that a second resolver cannot drift from the first.
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.
- 1mo ago First seen · 100 lines · 32 tokens per session scan A 7e6ba37e6fc4
tdd-worker is an agent published in the GitHub repository markshust/hcf (81 stars, last pushed 11d ago), licensed MIT. It adds 32 tokens to every session and 893 once invoked, about $0.0001 per session on Opus 5.5. 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 agents, from other repositories
implementer
Per-story implementation agent. Implements exactly ONE user story from quantum.json following TDD methodology. Spawned fresh for each story with no memory of previous iterations.
tdd-orchestrator
TDD orchestrator. Delegate only when the user explicitly starts an Octopus workflow.
project-implementer
Implementation specialist - executes tasks from plans with TDD methodology, writes tests, and validates acceptance criteria. Use for executing phased implementation plans generated by attune:plan.
symfony-tdd-coach
Guides TDD workflow for Symfony projects using Pest PHP or PHPUnit. Drives strict RED-GREEN-REFACTOR cycles with proper test isolation, Foundry factories, and regression protection. Use when writing tests, adding test coverage, or practicing TDD.
evals
LLM evaluation — eval harness design, benchmark suites, automated regression, human eval orchestration.
unfolding-po
PO (Product Owner) role in the Unfolding Specs process. Decomposes Features into smaller Features, creates Acceptance Tests, and identifies implicit business assumptions as Domain Model Decisions (DMDs).