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

Beyond the readOnlyHint annotation, the description discloses a non-obvious behavioral trait: assignment and active-package status are per project, so the same organization package can be active in one project and absent in a sibling. This provides useful context that annotations alone do not convey. The 'Read-only' confirmation is consistent but redundant with the annotation.

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?

The description is organized with purpose, use case, alternatives, and parameter semantics all present, and each sentence earns its place. It is slightly longer than strictly necessary because the per-project semantics appear in both the schema and the description, but it remains efficient and readable.

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 simple one-parameter, read-only tool with no output schema, this description provides a fully sufficient picture: return fields, decision context, sibling routing, and the key per-project behavior. The output schema absence does not leave an information gap because the description enumerates the return fields.

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%, and the project_id parameter schema already describes the UUID format, per-project semantics, error behavior, and plan limits. The description adds only framing ('the only argument', 'does more than filter'), which is helpful but adds minimal new meaning over 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?

The description states a specific verb and resource ('Lists'), the exact fields returned (name, version, description, active marker), and clearly differentiates from list_components and get_component. An agent can tell exactly what this tool does and how it differs from its siblings.

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 says when to use the tool ('to decide which npm package to import from', 'before calling get_component_updates') and what NOT to use it for, pointing to list_components and get_component as the alternatives. This is full usage guidance with no ambiguity.

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