tailtest CLAUDE.md

tailtest CLAUDE.md is an instructions file for coding agents from avansaber/tailtest. It costs 7,383 tokens per session, scanned A, original, MIT.

A set of instructions for tailtest, a testing tool that creates realistic test situations for recently changed code and runs them.

In plain words
What is it for?
Use it after building or changing code to verify the real interfaces, generate test scenarios, execute them, and track unfinished test work.
Why use it?
It reduces errors caused by writing tests for functions or imports that do not actually exist, and highlights only the failing scenarios.

Instructions file

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 instructions/avansaber/tailtest/claude-md
Clone the repo
git clone --depth 1 https://github.com/avansaber/tailtest

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 tailtest CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/avansaber/tailtest/claude-md.svg)](https://agentmods.dev/instructions/avansaber/tailtest/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/avansaber/tailtest/claude-md"><img src="https://agentmods.dev/badge/instructions/avansaber/tailtest/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 7,383 This file is loaded in full into every session.
When invoked 7,383 The same file — it is already loaded in full.
Security scan A 1 finding. 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 $0.07383 $0.07383
Opus 5 $0.03691 $0.03691
Sonnet 5 $0.01477 $0.01477
Haiku 4.5 $0.00738 $0.00738

Measured 3d ago against content hash ec88608cff60, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

tailtest CLAUDE.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 3d 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.

Not just `requests` / `axios`. Include `smtplib`, `socket`, `urllib`, `http.client`, `ftplib`, `imaplib`, and any `subprocess` call reaching an external process.
CLAUDE.md · 426 lines

How it starts

The opening of the file, as written. The whole thing — 426 lines — stays where its author put it; the contents beside it link to each section on GitHub.

tailtest

You are running with the tailtest plugin. Your job: automatically run the test cycle the user would otherwise ask for manually. Generate production-like scenarios for what was just built, execute them, and surface only what fails.


Step 0: Verify APIs before writing test code

Before writing any test code, read the source file and confirm:

  • Every class, function, and method you plan to call in the test actually exists in the module
  • Every import resolves to a real name in the file

Scope: verifies imports resolve and named attributes exist. Does not validate full call signatures. If a method does not exist, do not invent it -- adjust the scenario to test what actually exists.


Step 1: At the start of every user turn, check for pending work

Read .tailtest/session.json. If pending_files is non-empty:

Before generating: re-read the source file to understand what it actually does. Derive scenarios from the source's intent and behaviour -- not from your implementation plan or assumptions about what should exist.

  1. Note the pending files list
  2. Skip any filtered files (filter rules in Step 2)
  3. If nothing remains after filtering: clear pending_files to [], proceed to the user's message
  4. Before generating, check for ramp-up framing: if session.json has "ramp_up": true, count the entries whose status is "ramp-up" (call this N). If N > 0 and all remaining pending_files entries have status: "ramp-up" (pure ramp-up batch, no mixed new-file entries), emit exactly one line now: tailtest: running initial coverage scan on {N} file(s)... If the batch is mixed (contains both "ramp-up" and "new-file" entries), skip the framing line.
  5. Generate scenarios for all remaining files as one unit of work -- treat "ramp-up" entries identically to "new-file" (generate scenarios, write test, execute, report)
  6. Write test file and execute (Steps 4–5)
  7. Report failures -- stay silent if all pass (Step 6)
  8. Write "pending_files": [] back to .tailtest/session.json
  9. Then address the user's message

Read the full file on GitHub · 426 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. 3d ago First seen · 426 lines · 7,383 tokens per session scan A ec88608cff60

Subscribe to this mod's changes

tailtest CLAUDE.md is an instructions file published in the GitHub repository avansaber/tailtest (11 stars, last pushed 2mo ago), licensed MIT. It adds 7,383 tokens to every session, about $0.0369 per session on Opus 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 2026-08-31.