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

Annotations only declare readOnlyHint=false, so the description carries most of the behavioral burden. It does disclose the confirm-gate ('previews until confirm: true') and that no logging occurs, but it is silent on whether an existing plan is replaced, what permissions are required, or what the preview contains — though the confirm parameter description already covers the preview behavior.

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 core action is front-loaded in the first sentence, with the exclusion and the confirm-gate note following. Three compact clauses with no filler, though the parenthetical partially duplicates the schema's confirm description.

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 mutation tool with a nested schema, no output schema, and only a readOnlyHint annotation, the description covers source and confirmation but omits overwrite semantics and the shape of the result. Adequate but with clear gaps an agent might hit when assigning to a client who already has a plan.

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 50%, and the description only implicitly maps 'existing import' to importId and 'workout or diet plan' to kind. It adds no meaning for clientId, title, startDate, or endDate, leaving half the nested parameters documented solely by terse schema fields.

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 ('Assign') and a precise resource ('the PDF of an existing import itself as the client's workout or diet plan'), and clarifies nothing is logged. It differentiates from the upload path in spirit ('Uploading a new PDF is done in the app') but never names the sibling share_uploaded_pdf_plan, so an agent must infer which of the two to call.

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?

Gives a clear usage condition (you already have an import) and an explicit exclusion ('Uploading a new PDF is done in the app'), which steers the agent away from the upload flow. It stops short of naming an alternative tool or stating prerequisites such as the import having been processed.

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