Docs that describe a file

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely non-structured context: 'Deterministic, bounded, no model' tells the agent results are static analysis with no LLM inference, which signals reliability and repeatability beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single sentence, front-loaded with the question it answers and then a compact enumeration of return categories. Dense but every clause earns its place by naming a distinct result type; only the length of the enumeration keeps it from a 5.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so the description carries the return-shape burden, and it does so by enumerating the result categories along with the review state for covers= sections. Combined with 100% schema coverage on inputs, an agent has enough to call and interpret it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and both parameters (path, projectDir) carry clear schema descriptions with examples, so the description does not need to restate them. It adds no format or syntax detail beyond the schema, making the baseline 3 appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Opens with a verbatim question the tool answers ('which documentation describes this file?') and then enumerates the concrete result categories: canonical doc lines with heading/anchor/section, AGENTS.md/CLAUDE.md/GEMINI.md lines, @implements/@req IDs, @doc annotations, and covers= sections. This is specific enough to distinguish it from siblings like docguard_doc_structure and docguard_read_section.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The question framing implies when to reach for this tool (a per-file 'who documents this?' lookup), but there is no explicit when-not guidance and no sibling is named as the alternative. The agent must infer the selection criteria from the other tools' names.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.