close_session

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

Annotations already declare readOnlyHint=false and destructiveHint=false, and the description is consistent with a mutating teardown. It adds that session resources are released, which is useful beyond the annotations, but it omits key behavior: what happens to the session_id afterward, whether subsequent calls fail, and error behavior given idempotentHint=false.

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?

A single, front-loaded sentence with no filler. Every word earns its place and the effect (releasing resources) follows the action clearly.

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 one-parameter teardown tool with no output schema this is minimally adequate, but it leaves the post-close state undefined (is the session invalid, must a new session be opened, what happens on a repeat call given non-idempotent annotations). A sentence on the resulting session state would close the gap.

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?

Only one parameter, with 0% schema description coverage, so the description is the only place to explain it — and it never mentions session_id. The schema does provide format=uuid and a pattern, which makes the parameter's shape largely self-evident, so the description does not need to compensate heavily; a baseline 3 is appropriate.

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?

States a specific verb (close) and resource (browser context/session) plus the side effect of releasing resources. It is clear on its own, but it does not position itself relative to any sibling because none of the listed siblings (open_url, navigate, screenshot, etc.) perform session lifecycle operations, so no explicit differentiation is offered.

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 no guidance on when to call this versus alternatives, no prerequisites, and no indication of what state the session must be in beforehand. The agent must infer the lifecycle context entirely.

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