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

Goes well beyond the readOnlyHint/openWorldHint annotations by disclosing the retrieval backends (Wikipedia + searxng), the fact that it returns sources without a verdict, and a real auth constraint: it requires a personal Storskarvia API key as a Bearer token and is not an open retrieval API. That is exactly the kind of context an agent cannot get from structured fields.

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-loads the step and purpose, then adds constraints and auth. Three short sentences with no filler, though the parenthetical backend list and auth aside could be tightened slightly.

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?

An output schema exists, so return values need not be detailed, and the description confirms it returns sources. Auth requirements and behavioral boundaries are covered. Minor gap: no guidance on claim input constraints or on handling empty/insufficient retrieval results.

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?

There is one parameter, 'claim', with 0% schema description coverage. The description implies the one-claim-at-a-time granularity ('for one claim'), which adds some meaning, but says nothing about expected format, length limits, or whether multiple claims can be passed. Adequate but thin for a zero-coverage schema.

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 ('Runs ... server-side retrieval ... for one claim and returns the sources') and places itself precisely in the pipeline as 'Step 2' of the fact-check, which separates it from prepare_factcheck and submit_findings. It also explicitly declares what it does not do ('no verdict, no judgment'), removing ambiguity about its role.

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 clear operational context: use during the bring-your-own-agent fact-check flow and judge the claim ONLY against the returned sources, never outside knowledge. It stops short of naming the sibling tools or stating the precondition that the claim must first be prepared, which is left to be inferred from 'Step 2'.

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