Check up to 100 domains at once against the CRED-1 credibility dataset and return per-domain results, flagging any domains not found in the dataset.
Check multiple domains at once (max 100). Returns an array of results with the same fields as check_domain. Domains not found in the dataset are included with a "not_found" flag.
| Name | Required | Description | Default |
|---|---|---|---|
| domains | Yes | Array of domain names to check. |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the transparency burden and usefully discloses that the return is an array matching check_domain fields and that missing domains are included with a 'not_found' flag. It does not state explicitly that the operation is read-only, nor does it cover error handling for invalid entries, leaving some behavioral gaps.
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?
Three short sentences, front-loaded with the batch purpose and limit, then return shape and missing-domain behavior. No filler or repeated schema details beyond what is useful for orientation.
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?
For a simple one-parameter tool with no output schema, the description explains the return structure by reference to check_domain and covers the important missing-domain case. Minor gaps such as result ordering and duplicate handling remain, but the definition is sufficient to call the tool correctly.
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 schema already documents the domains array and maxItems=100. The description repeats the max-100 limit but adds no new parameter semantics such as expected domain format or duplicate handling, so the baseline 3 is appropriate.
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?
The description states a specific batch operation ('Check multiple domains at once') and distinguishes it from the single-domain sibling by naming check_domain. However, 'check' does not explain what is being checked beyond implied dataset membership, so the purpose is clear at the batch-vs-single level but not fully specified.
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?
'Check multiple domains at once' and the max-100 limit give clear guidance on when to use this batch tool rather than a single-domain call. It does not explicitly say to use check_domain for one domain or search_domains for discovery, so alternatives are implied rather than fully stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.