verify_news

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

With no annotations, the description carries the full burden and does so: it discloses the search-across-providers behavior, the two-publisher corroboration threshold (or one primary/official source), the is_legit=false default, and the aggregator-redirect edge case that counts for corroboration but is rejected by build_schema. This is unusually rich behavioral context.

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 2' role and the core verification rule, then the alternative and downstream feeding. Every sentence earns its place, though it is dense enough that a couple of clauses could be tightened.

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?

Despite no output schema, the description names the key return fields (is_legit, fetchable_urls, reference_candidates) and explains the pass/fail rule, which is what an agent needs. Minor gap: the effect of the `limit` parameter is left unexplained.

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%, so the description must compensate. It explains `days` ('limits how far back to look') and implies `title` is the headline under test, but `limit` is never mentioned and the title format/expectations remain unspecified. 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+resource ('confirm a SPECIFIC headline is real and corroborated') with an explicit scope distinction: 'This verifies a headline; it does not find one.' This contrast against find_stories lets an agent route correctly without opening sibling schemas.

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?

Explicit when-to-use routing: 'If the user gave you a topic ... call find_stories first,' plus a hard gate ('Do not draft anything if is_legit is false'). It also names downstream consumers (fetch_article_facts, build_schema) with the exact fields to pass, so usage is fully specified.

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