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

Annotations already declare readOnlyHint=true and destructiveHint=false; the description reinforces this in plain language ('opens nothing by itself') and adds what the response actually contains (screens, buttons, fields). That is useful beyond the annotations. It does not describe failure modes or what happens if the browser session is unavailable, but the key behavioral trait is disclosed.

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 operative information (returns instructions, does not act, use cotlet_browser_* to execute) is front-loaded and clear. However, the trailing note about Inoreader's REST API, OAuth 2.0 and the absence of an official MCP server is contextual trivia that does not help an agent call the tool, and 'from ChatGPT, Claude or any AI agent' is filler.

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 and no output schema, the description carries the burden of explaining the return value, and it does so (step-by-step screen/button/field guidance). It also tells the agent how to complete the real task via browser tools. Only the trivial API-status sentence is surplus, so it is nearly complete.

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 the schema-facing baseline is 4. The description correctly implies no inputs are needed and instead explains what artifacts the caller receives. Nothing is misleading about the parameterless signature.

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 action (add a feed to the user's Inoreader account) and then immediately clarifies that the tool itself only returns step-by-step UI instructions, which resolves the tension with the action-oriented name. It names the follow-up mechanism (cotlet_browser_* tools) so an agent can tell it apart from sibling inoreader_* tools. It stops short of explicitly contrasting with those siblings by name.

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?

Clear context is given: call this to learn the Inoreader procedure, then perform it with cotlet_browser_* tools in the Inoreader Cloud Browser. This is real when-to-use and what-to-do-next guidance. There is no explicit statement of when NOT to use it (e.g. if the feed is already subscribed), so it falls short of a 5.

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