Browser capabilities

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and non-destructive behavior on which the description builds. The description adds useful context about default output (action names, categories, compact runtime state) and how passing filters changes the response, which goes beyond the annotations without contradicting them.

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 description is two sentences with no filler. It front-loads the core purpose, then gives clear, compact usage rules. Every clause earns its place and no information is redundant with the schema or annotations.

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?

Given the tool's low complexity, fully optional parameters, rich annotations, and an output schema, the description is complete enough for an agent to call it correctly. It explains the default behavior, the effect of filters, and when to request full detail, leaving no critical gaps.

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 0%, so the description must carry the parameter semantics. It explains the roles of 'actions' and 'categories' for focused metadata and 'detail' for full reference retrieval. While it does not exhaustively describe every parameter, it provides meaningful guidance that maps directly to the schema fields.

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 a specific verb and resource: 'List browser relay actions and runtime availability.' This clearly identifies the tool as a metadata/listing operation and distinguishes it from siblings like browser_action or browser_snapshot, though the term 'browser relay actions' is somewhat jargon-heavy and the distinction is implied rather than explicit.

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?

The description provides actionable usage guidance: pass only intended action names or categories for focused metadata, and request full detail only when the entire reference is needed. It does not explicitly compare against sibling tools or state exclusions, but the parameter-level guidance is clear and practical.

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