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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context: it is free, it opens no browser session, and it degrades gracefully to a general method for apps outside the catalog. It does not describe response shape, but with no output schema that is a modest gap rather than a critical one.

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 content is dense but every clause carries information: return contents, the call-timing rule, the fallback for uncatalogued apps, and the no-session cost. It is a single long run-on sentence, so the front-loading is weaker than if the call-timing rule came first, but there is no 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?

For a read-only guide-retrieval tool with no output schema, the description enumerates what comes back (browser choice, sign-in link, method, screens/menus/actions, notes, dedicated tools), when to call it, and how it behaves for unknown apps. An agent has everything needed to decide to call it and to act on the result.

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?

Schema description coverage is 100% — both 'app' (name or Cotlet slug, default Clear Estimates) and 'task' (the user's goal in their words) are documented in the schema itself. The description adds only indirect hints, such as that the guide is tailored to 'this workspace' and the app's dedicated tools. That is baseline-level value, not enrichment.

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 concretely what the tool returns: which browser to use for the workspace, the sign-in link, a step-by-step method, screens/menus/actions, notes, and any app-specific Cotlet tools. That is far more specific than a tautology, and it implicitly separates the tool from the cotlet_browser_* siblings by being the preparation step. The only weakness is that the opening is a noun phrase ('How to work in an app...') rather than a direct verb+resource statement, which slightly blurs whether it fetches a guide or performs an action.

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 an explicit trigger: 'Call it before the first browser step in an app', which tells the agent exactly where in a workflow to invoke it. It also covers the edge case of apps outside Cotlet's catalog, which still get the general method. There is no explicit 'do not use when' clause or named alternative for app discovery (e.g. cotlet_apps), but the usage context is clear.

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