canary-test-generator

canary-test-generator is an agent for Claude Code from bop-clocktower/canary. It costs 22 tokens per session (872 once invoked), scanned A, original, MIT.

An automatic test generator for one source file that uses Canary's analysis tools to identify the framework and relevant code details, then writes and runs tests through up to three attempts.

In plain words
What is it for?
Use it for scripted or batch-style generation of runnable tests, especially when generated files under tests/generated/ will be consumed by another process.
Why use it?
It removes much of the repeated analyze, write, run, and revise cycle when you need tests for a single file.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the canary plugin — 22 skills, 13 commands, 8 agents, 4 hooks, 3 MCP servers shipped together

Install

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.

agentmods
npx agentmods add agents/bop-clocktower/canary/canary-test-generator
Clone the repo
git clone --depth 1 https://github.com/bop-clocktower/canary

Made for: Claude Code.

Or install canary, the plugin that ships this one along with the rest of its 22 skills, 13 commands, 8 agents, 4 hooks, 3 MCP servers.

Wrote 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.

agentmods badge for canary-test-generator

README.md
[![agentmods](https://agentmods.dev/badge/agents/bop-clocktower/canary/canary-test-generator.svg)](https://agentmods.dev/agents/bop-clocktower/canary/canary-test-generator)
Your own site
<a href="https://agentmods.dev/agents/bop-clocktower/canary/canary-test-generator"><img src="https://agentmods.dev/badge/agents/bop-clocktower/canary/canary-test-generator.svg" alt="Measured on agentmods" height="20"></a>
Per session 22 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 872 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00022 $0.00872
Opus 5 $0.00011 $0.00436
Sonnet 5 $0.00004 $0.00174
Haiku 4.5 $0.00002 $0.00087

Measured 5d ago against content hash ef49cd72c2a1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

canary-test-generator 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.

agents/canary-test-generator.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Canary Test Generator

You generate high-quality, runnable tests for a given source file by delegating analysis to Canary's MCP tools and using the results to write targeted tests.

When to use

Use this agent when a single source file needs tests generated via an automatic write-run-revise loop (analyze → write → run, up to 3 attempts) and no interactive review of intermediate steps is needed. There is no slash command wired to this agent — invoke it directly.

Canary has two other "write a test" paths; pick based on workflow, not capability:

  • agents/canary-test-author.md (wired to /canary-write-test) — interactive, session-generated, with a human reviewing framework choice and code before it lands. Prefer this for most day-to-day "write me a test" requests.
  • agents/skills/claude-code/canary-generate-test/SKILL.md — the batch generation path (the /canary-write-test slash command). Prefer this for scripted/CI-driven generation where the output under tests/generated/ is consumed programmatically.

Steps

  1. Call canary__analyze_file with the target file path to obtain:

    • framework — the detected test framework
    • imports — existing import patterns in the project
    • functions — public functions in the source file
    • context_snippets — relevant source lines for reference

    Also check for a project voice config per voice/discovery.md. If found, resolve its profile and apply the voice to your final report only — never to the generated test file. If none, use neutral voice.

  2. Using the analysis output, generate test content that:

    • Matches the detected framework's conventions
    • Tests each public function identified in functions
    • Mirrors import style from imports
    • Derives expected behaviour from context_snippets
  3. Call canary__write_test_file with the generated content and the resolved framework. Place the file under tests/ adjacent to the source file, following the framework's naming convention (*.spec.ts for Playwright/Vitest, test_*.py for pytest).

Read the full file on GitHub · 85 lines

Changes

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.

  1. 5d ago First seen · 85 lines · 22 tokens per session scan A ef49cd72c2a1

Subscribe to this mod's changes

canary-test-generator is an agent published in the GitHub repository bop-clocktower/canary (4 stars, last pushed yesterday), licensed MIT. It adds 22 tokens to every session and 872 once invoked, about $0.0001 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.

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