fetch_article_facts

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 and does well on failure semantics: failed fetches are reported per_url with a reason and never fabricated. It also bounds quote length (<=15 words). Missing: net/HTTP behavior, rate limits, or whether it makes network calls that could be slow/blocked.

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 step and core action, then return shape, then failure handling, then the usage contract. Four short paragraphs, each earning its place. No redundant restatement of the name.

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?

No output schema exists, so the description must describe returns and it does: facts, quotes, figures, tagged by source_url, plus a per_url failure report. For a two-parameter tool with no annotations, this covers the critical contract. The untouched max_facts_per_url is the main gap.

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% for two parameters (urls, max_facts_per_url), so the description should compensate. It obliquely defines what comes back per URL and the per_url failure structure, which hints at the urls list semantics, but says nothing about max_facts_per_url or batching. Partial compensation only.

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 and resource pair: download verified sources and extract usable material, then names the exact output (facts, quotes, figures). The 'Step 3' marker situates it in a pipeline, but the name alone could be read as purely a fetch operation; the description clarifies the extraction role. It does not differentiate from siblings like verify_news, which produces the 'verified sources' this tool presumably consumes.

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?

Gives explicit downstream constraint: everything written must trace back to this output, and out-of-output claims are excluded. This tells the agent when the output is authoritative. However, it never names or excludes sibling tools (verify_news, draft_brief) or states prerequisites for input URLs, so alternative selection remains implicit.

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