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

Annotations already declare readOnlyHint=true, openWorldHint=false, idempotentHint=true, and destructiveHint=false. The description adds meaningful behavior beyond that: it explicitly states it 'opens nothing by itself' and that the actual work must be done with cotlet_browser_* tools, plus it explains why (Zoopla has no public API). That's useful operational context, though rate limits, latency, or the exact shape of the returned guide are not described.

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 single most important fact, that this returns instructions and does not perform the action, is in the second sentence rather than front-loaded; the opening line 'List my listings' can mislead until the reader continues. There's also low-value filler such as 'from ChatGPT, Claude or any AI agent' and the verbatim date '(checked 11 Oct 2026)'. The content is accurate but not tight.

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, the description must describe the return value, and it does: a step-by-step guide covering screens, buttons, and fields. It also explains the follow-up workflow via the browser tools. What's missing is any mention of how the guide is structured/verified or what to do if the browser tools fail, but for a zero-parameter guide tool this is largely 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?

This tool takes zero parameters, so the schema carries nothing to misinterpret and the baseline is the maximum here. The description correctly requires no parameter explanation. It adds only the implicit scoping that the listing account is 'the user's own', which is consistent with the empty 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 specifies the resource (the user's own Zoopla listings) and, crucially, clarifies that the tool returns a step-by-step procedure rather than the listing data itself: 'Returns how to do it in Zoopla step by step (screens, buttons, fields)'. That resolves the mismatch between the name and the actual behavior. It stops short of a 5 because it does not distinguish itself from sibling guide/diagnostic tools such as cotlet_app_guide or zoopla_get_listing_stats.

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?

There is usable guidance embedded: use this tool to get the steps, then 'do it with the cotlet_browser_* tools in the user's Zoopla Cloud Browser'. That gives a clear follow-on workflow. However, there is no explicit when-not guidance or named alternative for a user who actually wants listing data/stats, and neighbor tools like cotlet_app_guide are never mentioned as alternatives, so the routing is implied rather than complete.

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