isbn_checkValidate an ISBN-10 (mod-11) or ISBN-13 (1,3-weight mod-10) checksum.
| Name | Required | Description | Default |
|---|---|---|---|
| isbn | Yes | ISBN-10 or ISBN-13; dashes/spaces allowed. |
| Name | Required | Description | Default |
|---|---|---|---|
| tool | No | ||
| scope | No | ||
| valid | Yes | ||
| reason | Yes | ||
| country | No | ||
| normalized | No |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds concrete algorithm details (mod-11,1,3-weight mod-10), making the deterministic behavior transparent without promising side effects or extra behavior.
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 a single,front-loaded sentence that names the action and scope immediately, then adds only the algorithm details needed to disambiguate. There is no filler or repetition.
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 one-parameter, deterministic validation tool with an output schema and read-only annotations, this description is complete. The agent can understand what it validates, how it validates, and the schema covers inputs and outputs without the description needing to repeat return semantics.
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 input schema has 100% coverage; it already tells the agent the ISBN can be ISBN-10 or ISBN-13 and that dashes/spaces are allowed. The description adds no parameter-specific meaning beyond that, so the baseline of 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 uses a specific verb ('Validate') and a precise resource ('ISBN-10/ISBN-13 checksum'), and even names the exact algorithms (mod-11 and 1,3-weight mod-10). This clearly differentiates it from generic sibling tools like luhn_check or ean13_check without requiring schema inspection.
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 clearly establishes the tool's context: validating ISBN-10/ISBN-13 checksums. It gives enough information for an agent to select it among many sibling check tools, but it does not explicitly mention alternatives or exclusion cases, so it stops short of a 5.
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.
Each tool targets a distinct identifier type or specific function (e.g., IBAN vs. EIN vs. block info), with no overlap even among similar validation routines. The batch and rental tools combine distinct sub-checks without ambiguity, making misselection unlikely.
Tool names are uniformly snake_case and mostly follow a descriptive pattern, but the action verbs vary (e.g., 'check', 'format', 'info', 'guard', 'verdict') rather than a single verb_noun structure. While clearly readable, the pattern is not perfectly uniform.
At 28 tools, the server feels like a broad utility pack rather than a focused domain. The count exceeds the 'heavy' threshold and includes three distinct sub-domains (financial identifiers, rental fraud, on-chain queries), making the surface area hard to navigate coherently.
The identifier validation coverage is thorough (most common checksums), rental checks cover risk, deposit, and verdict, and on-chain tools handle balances, activity, and settlement history. Minor gaps exist (e.g., no token transfer history, no generic identifier detection) but agents can likely work around them.