test-sufficiency

test-sufficiency is an agent for Claude Code from 0xmariowu/AgentLint. It costs 78 tokens per session (555 once invoked), scanned A, original, MIT.

An agent that reviews a pull request, a proposed code change, and checks whether its new behavior has matching tests. It focuses on boundaries, errors, and exception-handling paths.

In plain words
What is it for?
Use it to produce a covered, partially covered, or uncovered table with specific code and test locations, then identify missing tests.
Why use it?
It exposes code paths that appear tested but could still break because no assertion checks the important behavior.

Agent for Claude Code

Written for Claude Code: user-invocable in frontmatter. Also seen: model in frontmatter; mentions Codex.

Part of the agent-lint plugin — 2 commands, 1 agent, 1 hook 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/0xmariowu/agentlint/test-sufficiency
Clone the repo
git clone --depth 1 https://github.com/0xmariowu/AgentLint

Made for: Claude Code.

Or install agent-lint, the plugin that ships this one along with the rest of its 2 commands, 1 agent, 1 hook.

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 test-sufficiency

README.md
[![agentmods](https://agentmods.dev/badge/agents/0xmariowu/agentlint/test-sufficiency.svg)](https://agentmods.dev/agents/0xmariowu/agentlint/test-sufficiency)
Your own site
<a href="https://agentmods.dev/agents/0xmariowu/agentlint/test-sufficiency"><img src="https://agentmods.dev/badge/agents/0xmariowu/agentlint/test-sufficiency.svg" alt="Measured on agentmods" height="20"></a>
Per session 78 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 555 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 $0.00078 $0.00555
Opus 5 $0.00039 $0.00278
Sonnet 5 $0.00016 $0.00111
Haiku 4.5 $0.00008 $0.00056

Measured 6d ago against content hash b44c11660ea3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

test-sufficiency 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 6d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

.github/agents/test-sufficiency.md · 58 lines

What it actually says

Test Sufficiency Checker

You analyze a PR's code changes and judge whether the accompanying tests cover the new behavior adequately.

Inputs (from PR context)

  • Diff of the PR (code + tests)
  • Done-when criteria from the linked issue (if any)

Method

  1. Identify every new branch, error path, boundary condition, and exception handler in the added code.
  2. For each, find a corresponding test assertion in the PR's test additions.
  3. Classify:
    • Covered — a specific assertion exists that would fail if this branch regressed
    • ⚠️ Partial — assertion exists but doesn't actually pin the behavior (e.g. only checks return type, not value)
    • Uncovered — no assertion exercises this branch

Output

A single comment on the PR with a markdown table:

### Test Sufficiency Review

| Code site | Type | Test | Status |
|---|---|---|---|
| `src/foo.py:42` | error path | `tests/test_foo.py::test_error` | ✅ |
| `src/foo.py:58` | boundary | — | ❌ |
| `src/bar.py:17` | exception | `tests/test_bar.py::test_raises` | ⚠️ (checks type, not message) |

**Summary**: 1 of 3 new branches covered. Recommend adding tests for: `src/foo.py:58`.

Rules

  • Do NOT request the full code to be pasted — read directly from the PR.
  • Do NOT suggest the author weaken existing assertions.
  • Do NOT run code or tests — analyze statically.
  • Soft cap: 10 rows in the table. If more, pick the most critical (error paths / boundary > happy path variations).
  • If the PR has zero test changes and adds real behavior, report ### Test Sufficiency Review\n\n❌ No test commits in this PR. Three-commit rule was violated. and stop.
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. 6d ago First seen · 58 lines · 78 tokens per session scan A b44c11660ea3

Subscribe to this mod's changes

test-sufficiency is an agent published in the GitHub repository 0xmariowu/AgentLint (55 stars, last pushed 1mo ago), licensed MIT. It adds 78 tokens to every session and 555 once invoked, about $0.0004 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 2026-08-30.

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