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

With no annotations, description must convey behavior. It discloses that no browser is launched, but does not say whether any network request happens, whether it's read-only, or that many accepted parameters are discarded. The schema descriptions reveal discard behavior, but the main description itself leaves the tool's operation ambiguous.

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?

Two terse sentences, front-loaded with the core action and a key caveat. No unnecessary words.

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?

The tool has a bloated input schema with unrelated params (city, ref, json, path) and no annotations or output schema. The description doesn't clarify why these exist or what an agent should expect as a result (boolean? status?). For a function whose core purpose is a simple check, this is under-specified.

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 covers all 7 params, many with explicit 'discarded' notes, so the description adds no parameter-level meaning. It doesn't identify url as the primary parameter or explain the presence of unrelated params. Baseline 3 applies because coverage is high.

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?

Description states 'Check whether a URL can be opened' – a clear verb and resource. 'No browser is launched' differentiates it from sibling playwright-url-ok. However, 'can be opened' is ambiguous between syntactic validation and network reachability, so not a 5.

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?

No mention of when to use this versus normalize-url, fetch-status, or playwright-url-ok. The description only states what it does, not when it's appropriate, so an agent is left without routing cues.

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