email_extractorExtracts emails from texts. x402 payment required (testnet USDC).
| Name | Required | Description | Default |
|---|---|---|---|
| texts | Yes | メールアドレスを探したいテキストの配列 | |
| dedupe | No | ||
| payment | No | x402 payment payload (base64 JSON), signed EIP-712 exact/transferWithAuthorization. Omit on the first call — the tool will return payment requirements (accepts[]) as an error result. | |
| maxPerText | No |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
There are no annotations, so the description carries the full burden. It discloses that payment is required, which is useful, but it omits critical behavioral details such as the need to call without payment first to receive 'accepts[]' requirements, or that it returns errors for missing payment. The schema's payment parameter covers some of this, but the description itself is thin.
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?
The description is extremely short and to the point, which is efficient, but it under-specifies important operational context like the payment flow. It is brief but not optimally structured because the payment mention is vague without details on the first-call behavior.
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?
The tool has 4 parameters, no output schema, and no annotations. The description is too minimal to guide an agent through the non-trivial payment workflow (first call without payment, receiving accepts[], then retrying with a signed payload). Important behavioral context 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?
The description adds no parameter semantics beyond what the input schema already provides. Schema coverage is 50% (texts and payment described, dedupe and maxPerText undocumented), and the description does not compensate for the missing parameter meaning or clarify how they behave.
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 clear verb ('Extracts') and resource ('emails from texts'), which accurately conveys the tool's core function. It does not differentiate from siblings because none are provided, but the purpose is specific enough for an agent to understand what the tool does.
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?
The description gives no guidance on when to use this tool or any alternatives. It does mention a payment requirement, which is a precondition, but does not explain the usage context, workflow, or any exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
The server exposes only a single tool, so there is no possibility of confusion between tools. With one tool present, the agent can always select the correct one without any ambiguity. This is inherently the highest level of disambiguation.
With only one tool, naming consistency is trivially satisfied—there are no other tools to compare against. The name 'email_extractor' clearly and accurately describes the tool's function, using a descriptive noun-based pattern that is self-consistent. As there is no mixed convention, consistency is perfect.
A single tool is borderline for a server's scope. While a simple utility like email extraction could be justified as a single-purpose service, it feels thin compared to typical use cases where multiple related operations (e.g., validation, batch processing) might be expected. This places it at the lower end of the appropriate range, earning a score of 3 rather than higher.
The core email extraction function is present, which directly addresses the server's stated purpose. However, there is a minor gap in that no supplemental operations such as deduplication, validation, or formatting are offered. This is not a critical gap, but it prevents a perfect 5, as the surface is just a single operation without any related utilities that would round out the domain.