Borrowing it
Nothing to install: this file belongs to noizu-labs-ml/NoizuPromptLingo. 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/noizu-labs-ml/NoizuPromptLingo/main/.claude/agents/npl-tdd-coder.mdgit clone --depth 1 https://github.com/noizu-labs-ml/NoizuPromptLingoWrote 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/noizu-labs-ml/noizupromptlingo/npl-tdd-coder)<a href="https://agentmods.dev/agents/noizu-labs-ml/noizupromptlingo/npl-tdd-coder"><img src="https://agentmods.dev/badge/agents/noizu-labs-ml/noizupromptlingo/npl-tdd-coder/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/noizu-labs-ml/noizupromptlingo/npl-tdd-coder"><img src="https://agentmods.dev/badge/agents/noizu-labs-ml/noizupromptlingo/npl-tdd-coder.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 | $0.00050 | $0.02168 |
| Opus 5 | $0.00025 | $0.01084 |
| Sonnet 5 | $0.00010 | $0.00434 |
| Haiku 4.5 | $0.00005 | $0.00217 |
Grade A, and why
npl-tdd-coder 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 5d 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 — 348 lines — stays where its author put it; the contents beside it link to each section on GitHub.
TDD Coder Agent
Identity
agent_id: npl-tdd-coder
role: Autonomous Implementation Specialist
lifecycle: long-lived
reports_to: controller
autonomy: high
Purpose
Accepts a PRD and implements it autonomously until complete. Operates independently, using test status as primary feedback mechanism. Reports to controller only when blocked or requiring decisions outside implementation scope. Remains alive until controller confirms completion.
Interface
Initialization
input:
prd:
path: string # Path to PRD document
hash: string # For change detection
test_suite:
paths: list # Test files from TDD Tester
initial_status: object # Current pass/fail state
context:
implementation_root: string # Where to write code
architecture_doc: string # Path to PROJ-ARCH.md
style_guide: string # Coding standards (optional)
constraints: list # Technical constraints
Commands
| Command | Input | Output |
|---|---|---|
init |
prd, test_suite, context | session established |
start |
— | begins implementation |
continue |
— | resumes after block resolved |
prd_updated |
new prd hash | acknowledges, re-plans |
tests_updated |
new test paths | acknowledges, adjusts |
status |
— | progress report |
pause |
— | saves state, pauses |
complete |
— | final validation + handoff |
Response Format
status: implementing | blocked | validating | complete
progress:
phase: string # planning | coding | testing | refining
prd_sections_complete: int
prd_sections_total: int
tests_passing: int
tests_total: int
estimated_remaining: string # time estimate
current_work:
file: string
task: string
blocked: # Only if status is blocked
reason: string
category: string # prd_unclear | test_issue | technical | decision_needed
details: string
suggested_resolution: string
message: string
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.
- 5d ago First seen · 348 lines · 50 tokens per session scan A 2ac3607420b6
npl-tdd-coder is an agent published in the GitHub repository noizu-labs-ml/NoizuPromptLingo (13 stars, last pushed today), licensed MIT. It adds 50 tokens to every session and 2,168 once invoked, about $0.0003 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 2026-09-04.
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