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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description reinforces this with the concrete behavioral claim that it 'opens nothing by itself.' It goes further by disclosing the return content (step-by-step screens, buttons, fields) and the third-party constraint that Thumbtack's Partner Platform API is gated and request-only, explaining why browser automation is the path. It stops short of mentioning any setup prerequisite for the Cloud Browser or credit cost of browser sessions.

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 sentences, front-loaded with the purpose and the key correction about what the tool returns. The official-API sentence is useful justification for the browser approach but is denser than needed for invocation. No filler sentences, though the mid-clause placement of 'and opens nothing by itself' slightly buries the most important behavioral detail.

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 and no parameters, the description bears the burden of explaining what comes back, and it does: a step-by-step guide with screens, buttons, and fields, plus the handoff to cotlet_browser_* tools. Annotations cover the safety profile. What is missing is any note about prerequisites (an active Thumbtack Cloud Browser session) or failure modes, which keeps it below 5.

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 no parameter meaning to add beyond the empty schema; the baseline for a 0-param tool is 4. Nothing in the description misleads about inputs.

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 verb+resource (export past leads) and, crucially, corrects what the name implies by saying it 'Returns how to do it in Thumbtack step by step (screens, buttons, fields) and opens nothing by itself.' That resolves the ambiguity between a data-export tool and a guidance tool. It does not differentiate against the closest sibling for retrieving leads, thumbtack_list_leads, so it falls short of a 5.

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 follow-on guidance: use this to get instructions, 'then do it with the cotlet_browser_* tools in the user's Thumbtack Cloud Browser,' which tells the agent exactly how this fits into a workflow. It does not state when to prefer this over thumbtack_list_leads for lead data, so the alternative-selection guidance is incomplete.

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