List Modules

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds that the output is an aggregated grouping with counts rather than raw entities, which is useful context, but nothing about scale limits, cost, or result size.

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?

Three short sentences; the overview purpose leads, the grouping dimensions follow, and the usage cue closes. No padding or repetition of the schema.

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?

With no output schema, the description compensates by stating the return shape (groups with counts). It is sufficient for a two-param read-only aggregation tool, though the exact structure of the grouped result remains implicit.

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 the baseline is 3, and the description goes beyond it by clarifying that 'layer' means architectural layers such as route/service/component, giving the enum value concrete meaning the schema does not.

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 specific verb+resource (list/group symbols) and enumerates the grouping axes (layer, module, file, language) plus the returned counts. Clearly distinguishable from granular siblings like query_entities or get_entity, which fetch individual symbols rather than an organizational overview.

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?

Explicitly prescribes the use case: 'orient yourself in an unfamiliar codebase before diving into specifics,' and the schema points to list_projects for multi-project mode. It gives clear context but doesn't state when an alternative (e.g., query_entities) would be preferable once oriented.

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