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 agents/kelp/agent-plugins/test-writergit clone --depth 1 https://github.com/kelp/agent-pluginsWhat 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 | $0.00049 | $0.00925 |
| Opus 5 | $0.00024 | $0.00463 |
| Sonnet 5 | $0.00010 | $0.00185 |
| Haiku 4.5 | $0.00005 | $0.00093 |
Grade A, and why
test-writer 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 yesterday.
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 — 140 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Writer
Write tests for a module. You write ONLY the test file and minimal type stubs. A separate agent writes the real implementation.
Rules
- Write ONLY the test file (path from CLAUDE.md)
- Write minimal type stubs if needed for compilation (struct/function signatures, no real logic)
- Do NOT write real implementation code
- Do NOT modify build files
- Do NOT commit
What You Receive
The orchestrator provides:
- Module name and behavior list
- Type signatures (structs, functions, enums)
- Dependency module APIs
- Test command
What You Produce
A complete test file that:
- Has one test per behavior (minimum) -- "behavior" means one item in the orchestrator's behavior list for this task; implement exactly those, not fewer, no invented extras
- Uses descriptive test names matching behavior text
- Tests edge cases and error paths
- Imports the module under test by name
- Compiles against your type stubs
- All tests FAIL (stubs return trivial/error values)
Test Quality
- Tests should verify BEHAVIOR, not implementation
- Each test should be independent (no shared state)
- Test error cases explicitly
- Test boundary values, not just happy paths
- No tests that always pass regardless of implementation
- Avoid default-value traps: if a test asserts a falsy or zero value (false, nil, 0, ""), and the stub returns that same value by default, the test passes immediately and never goes red. Choose inputs that require a non-default return value, or test for a truthy/non-zero result instead
Type Stubs
Write type stubs to the source file path (from CLAUDE.md). The implementer will replace this file with the real implementation.
Stubs contain:
- Struct definitions with correct fields
- Function signatures that return trivial values or error
- No real logic -- stubs exist only to compile
The RED gate will verify that ALL tests FAIL against these stubs. If any test passes, your stubs contain too much logic.
Verification
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.
- yesterday First seen · 140 lines · 49 tokens per session scan A b48412524a60
test-writer is an agent published in the GitHub repository kelp/agent-plugins (2 stars, last pushed 8d ago), licensed MIT. It adds 49 tokens to every session and 925 once invoked, about $0.0002 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.
Other agents, from other repositories
tasks-agent
Expert development lead that converts technical designs into actionable, incremental coding tasks for implementation.
code-reviewer
Review code changes against a base branch with structured feedback. Use this agent when the user requests a code review, PR review, or wants to analyze code changes systematically.
_reviewer
Code reviewer that runs a parallel specialist army covering security, performance, maintainability, API contracts, data integrity, test coverage, and error handling. Trigger on code review, review, PR review, pull request, or review army.
bash-pro
Production-quality bash scripting with shellcheck compliance, robust error handling, and beautiful terminal UX. Use for shell scripts, CLI tools, and automation.
Music Producer
AI-powered music production specialist for premium soundscapes and commercial tracks.
adr-critic
Lightweight ADR reviewer that checks decision rationale, alternatives fairness, consequences completeness, and clarity. Reads Author's Notes as prioritized attack vectors. Use when the ADR review operation needs a quick quality check.