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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds that the listing covers 'all project file paths' and that filtering is optional, but says nothing about return shape, ordering, or size limits for large projects.

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 tight sentence with the core action front-loaded and no filler. The trailing parenthetical is slightly awkward but does not bloat the definition.

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?

For a 2-param read-only tool with no output schema and adequate annotations, the description is minimally viable. It is still missing the disambiguation an agent needs to choose it over list_files/search_files, which matters given the crowded sibling set.

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%, so both parameters are documented in structured data, establishing the baseline of 3. The description restates the optional nature of the filter but adds no format or matching semantics beyond 'substring or glob-ish filter' already in the schema.

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?

States a concrete verb and resource: 'List all project file paths', with the optional substring filter scoped. However, it does not differentiate itself from the closely-named siblings list_files and search_files, both of which plausibly do something similar.

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?

No statement of when to use this versus list_files or search_files, and no prerequisites or exclusions. The only hint is the parenthetical 'optional substring filter', which implies but does not guide usage.

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