pilot_set_cookie

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

No annotations are provided, so the description carries full burden. It discloses the domain scope ('on the domain of the currently active page'), security redaction of value in return, and an error case ('Cannot set cookie without a page'). Minor omission: no mention of expiration or overwrite behavior.

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?

Well-structured with sections for description, usage, parameters, returns, and errors. Every sentence is informative and concise, with no redundancy.

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 simple cookie setter without output schema, the description covers return behavior (confirmation with redacted value) and a key error scenario. Could optionally mention cookie attributes like path, but not essential for basic use.

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 descriptions are present (100% coverage) but the tool description adds concrete examples (e.g., 'session_id', 'theme', 'abc123', 'dark'), enhancing meaning beyond the schema alone.

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 explicitly states 'Set a cookie on the current page's domain with a given name and value,' clearly indicating the verb, resource, and scope. It distinguishes from the sibling pilot_import_cookies by contrasting manual vs bulk import.

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?

Provides explicit usage context: 'Use when the user wants to manually set a cookie for authentication, testing, or session management.' Also names a clear alternative: 'For bulk cookie import from a real browser, use pilot_import_cookies.'

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