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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, and the description usefully reinforces this by stating it "opens nothing by itself", so the agent understands it is a planning/guidance call rather than a mutation. The added note that CoachingPortal publishes no public API explains why the browser route is required, though it does not mention authentication or session prerequisites beyond "the user's own account".

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 workflow is front-loaded, but the closing line "CoachingPortal's official API: CoachingPortal publishes no public API" is redundant and awkwardly phrased, and restates the same fact twice. The second sentence packs two ideas (returns instructions; then execute via browser tools) without a clean break.

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 zero-parameter, no-output-schema tool, the description covers what is returned (step-by-step screens, buttons, fields) and how to act on it, which is sufficient. What is missing is minimal but real: prerequisites for the Cloud Browser session and clarification of what "pt workout" scope means versus the pt-session siblings.

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 and the description adds nothing about inputs, because there are none to describe. With 0 params, that is a limitation rather than a strength; the 4 baseline assumes no further semantic gaps, but here the description also fails to say what additional context might be needed (e.g., account or workout identity).

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 that the tool returns a step-by-step walkthrough (screens, buttons, fields) for logging a PT workout, which is a specific verb and resource. It implicitly distinguishes itself from the management siblings by emphasizing that it "opens nothing by itself", but it never names the actual alternative (e.g., manage_pt_session) that performs the write.

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 a clear usage path: call this first to get the instructions, then carry them out with the cotlet_browser_* tools in the Cloud Browser. It lacks explicit when-not-to-use guidance or a named sibling for cases where a direct management tool is preferable.

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