rtfm_coverage

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

With no annotations, the description carries the behavioral burden and does well: it clarifies that the denominator is the scan's file list, not the whole directory, and that excluded files are not counted as gaps. It does not disclose the return format, but the core measurement semantics are transparent.

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?

Four short sentences, each adding a distinct piece of information: purpose, usage trigger, denominator definition, and exclusion rationale. It is slightly discursive but not padded.

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?

The tool has no output schema and no annotations, so the description should clarify what the agent receives in return; 'how much ... holds' is suggestive but not explicit. It also leaves the optional parameter's 'current project' default to the schema. Overall it is adequate but incomplete.

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 coverage is 100%, so the schema already documents the optional 'project' parameter fully. The description adds no parameter-level detail beyond the schema, placing it at the baseline.

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?

The description answers 'how much of a project the index holds,' which identifies the tool as a coverage-measuring operation on a specific resource. It is distinct from the search/expand/context siblings in subject matter, though it does not explicitly compare itself to them.

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?

It explicitly instructs to invoke/mention coverage before answering from the index when completeness matters, giving a concrete condition of use. It does not name the sibling alternatives or state when not to use it, so it stops short of a 5.

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