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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, and the description is consistent with that, reinforcing that nothing is executed remotely. It adds genuinely useful behavioral context beyond annotations: the return shape (screens, buttons, fields) and the fact that a separate browser toolset must perform the real action. The oddly dated 'no public API' note adds rationale but is tangential noise.

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 compact sentences, front-loaded with the action and immediately followed by the crucial 'opens nothing by itself' caveat, then the handoff to browser tools. The trailing API/webhook note is the weakest sentence and could be trimmed, but it does explain why the browser route is required.

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 parameters, no output schema, and annotations covering safety, the description carries the return-value burden and does so by describing step-by-step instructions with screens, buttons, and fields. The only missing element is guidance on what happens if the user's account or browser session is unavailable.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and no schema-based gaps to fill. The description correctly implies a parameterless lookup, matching the empty input 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 names the concrete operation (assigning a program in the user's FitSW account) and then corrects the likely misreading by stating the tool 'returns how to do it in FitSW step by step ... and opens nothing by itself.' That distinction from an actual write action is the key information an agent needs, though the opening clause still echoes the title closely and could momentarily read as a mutation.

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?

It gives explicit sequencing: call this to get the steps, 'then do it with the cotlet_browser_* tools in the user's FitSW Cloud Browser,' which tells the agent both when to use it and what to reach for next. It does not contrast itself with adjacent siblings such as cotlet_app_guide or fitsw_create_workout, so an agent must infer that division of labor.

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