extract_metadata

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

No annotations are provided, so the description carries the full behavioral burden. It does not say whether the tool fetches the URL over the network, how redirects or unreachable/timeout URLs are handled, whether auth or robots restrictions apply, or whether a head-only request is made. 'Inspect' is the only hint about mechanism.

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?

One front-loaded sentence naming the tool's output, followed by a compact arg note with no filler. The 'Args:' block is slightly redundant with a single obvious parameter but is not wasteful.

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?

Output is covered by an output schema, so return values need no explanation, and a single required parameter keeps the surface small. The remaining gap is the absent behavioral detail around network access and failure handling, which matters for a URL-fetching tool but is minor given overall simplicity.

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 0% and the schema only types url as a bare string, so the description's 'Absolute http(s) URL of the page to inspect' meaningfully constrains the expected format. For a one-parameter tool this is adequate compensation, though it adds no detail on encoding or query-string handling.

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 ('Extract') and resource ('page metadata') and enumerates the extracted fields (title, description, author, Open Graph tags). It is distinguishable from fetch_url/fetch_urls, which retrieve content rather than parsed metadata, though it never names those siblings 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?

Usage is only implied by contrast with the sibling fetch tools: an agent can infer this is for metadata rather than full page content. There is no explicit when-to-use, when-not-to-use, or alternative routing statement.

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