session_cookies

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

Beyond the readOnlyHint annotation, the description discloses the return format, that cookies are scoped to the page's URL, and that the output round-trips with session_create's cookies field. This gives an agent practical behavioral expectations for a read-only export operation.

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 tight sentences: the first states purpose and output format, the second gives the concrete use case, and the third reinforces the round-trip contract. Every sentence earns its place, with 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 simple one-parameter read-only tool, the description is complete: it explains what is exported, the format, the URL scoping, and how to replay the cookies later. The lack of an output schema is mitigated because the return shape is explicitly described.

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 input schema fully documents session_id with 'Session ID', so the schema carries the parameter-semantics burden. The description does not add detail about how session_id affects the cookie export, so it stays at the baseline.

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 names a specific verb ('Export'), a precise resource ('the session's current cookies'), and the exact output shape ('["name=value", ...]') for the page's URL. This clearly distinguishes it from broader siblings like session_export or session_state.

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 explicitly states when to use the tool: 'Use to persist a logged-in session and replay it later via session_create with cookies.' It points to the relevant sibling session_create, though it does not explicitly mention when not to use it or contrast it with session_export.

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