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

No annotations are provided, so the description carries the burden. It reveals behavioral traits: enables Runtime, auto-selects the active tab, and returns pageId/pageUrl for verification. It does not mention permissions or side effects, but for a CDP evaluation, these are reasonable to expect.

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 three sentences, each conveying essential information: what it does, how it works, and a caveat about page identity. No filler; front-loaded with the core action.

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 moderate complexity acceptably complete. It covers the main purpose, the key behavioral nuance (pageId), and the return fields. It doesn't document the output schema (none provided), but for an evaluation tool, specifying result value and exception details is sufficient.

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 100%, so parameters are well-documented. The description adds context for pageId (auto-picked when omitted) and the return fields, but does not elaborate on expression syntax or awaitPromise behavior beyond schema defaults.

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 clearly states the tool evaluates a JavaScript expression in a page context via CDP, specifying the mechanism (enabling Runtime, calling Runtime.evaluate). It is distinct from siblings like android_devtools_get_dom or android_devtools_elements and identifies the tab context explicitly.

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 explains when to use it (after a navigate, auto-selects the active tab) and gives a hint on when to check results (if they seem from the wrong page). It doesn't explicitly name alternatives like web_evaluate or ios_safari_evaluate, but the context (android_devtools_ prefix) implies device-specific usage.

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