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

Adds substantial behavioral detail beyond the readOnlyHint/openWorldHint annotations: pages come through proxied browser renderers, the service does not bypass auth/access controls, and paywalled=true is set when only a teaser is public. This tells the agent what to expect in failure/partial-content cases.

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?

Front-loaded with the core action, then behavior, then the sibling pointer; every sentence earns its place. The url restatement is slight redundancy with the schema but not costly.

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?

Return values are covered by the output schema, and the description fills the remaining gaps: sourcing via proxied renderers, auth boundaries, and the paywall flag. Nothing material an agent needs to call it correctly is missing.

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% and the single url parameter is already documented, so the description's 'url: Canonical SFGate article URL' merely repeats the schema. Baseline 3 is appropriate with no added syntax or format guidance.

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?

Specific verb ('Returns') plus resource ('public SFGATE article metadata and body paragraphs') and input ('from a canonical article URL'). It also names a sibling (sfgate_headlines), so an agent can distinguish it from the headline/author/section family without opening the schema.

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?

Explicitly routes the agent to sfgate_headlines for section headlines and implies the input must be a canonical article URL. It gives a clear context for use but stops short of stating when-not-to-use (e.g. what to do with a non-canonical or non-SFGATE URL).

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