browser_close

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

With no annotations, the description carries the full burden and does well: it discloses the side effect that empty episodes are not recorded, that result overrides the automatic verdict, and that a verdict is produced. It stops short of saying whether closing can fail, whether the tab state persists, or what the returned episode contains.

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?

Four tight sentences, each doing distinct work, and the primary action is front-loaded before the result semantics and the lesson_record pointer. Nothing is redundant with the schema.

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 2-parameter tool with no output schema, the description covers what is returned (the episode verdict), the null-episode edge case, and the follow-up workflow. The remaining gap is sibling selection against browser_close_mine, which matters given how similar the names are.

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 coverage is only 50% and the description compensates: it explains that result declares success/partial/fail and overrides the automatic verdict, which is meaning the bare enum does not convey. The tab parameter is already documented in the schema as the id from browser_open, so no loss there.

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 and resource ('Close a tab') plus a scope qualifier ('this server opened') and the outcome it returns ('episode verdict'). It does not distinguish itself from the sibling browser_close_mine, which is the one ambiguity an agent would want resolved.

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 real guidance on the result parameter and on when to reach for lesson_record ('if something tripped you up'), which implies usage context. However, it never states when to use this versus browser_close_mine or when closing is inappropriate, so the routing decision is left to inference.

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