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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so safety is covered. The description adds value beyond that by disclosing sort order ('newest first') and the exact payload contents (status, current version, progress, pending amendments), which orientations the agent correctly.

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?

One well-formed sentence that front-loads the action and scope, then enumerates return fields. Dense and mostly waste-free, though the parenthetical explaining progress calculation is slightly verbose for a description that could push that into 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 carries the burden of describing returns and does so thoroughly, including the status vocabulary. Missing only secondary operational details such as result limits or pagination for a list tool.

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 0% and the single 'project' parameter has only a default of empty string, so the description must compensate. It does establish that the parameter is an optional single-project filter, but never says whether the value is a project name, ID, or slug, leaving ambiguity.

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 and resource ('Lists the user's plans') and goes further by enumerating the returned attributes, including the status enum values. It does not explicitly distinguish itself from near-siblings like plan_status or plan_current_step, so an agent may need to compare schemas to be sure.

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?

'optionally for one project' hints at the filter use case and the default behavior (all plans), which is useful implied guidance. However, there is no statement of when to reach for this versus plan_status, plan_current_step, or plan_list alternatives, and no exclusions.

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