USE THIS to verify a Finnish henkilötunnus (HETU / personal identity code) before relying on it — do not guess the check character. Checks the DDMMYY + century sign + individual number + mod-31 check character. Validates structure only.
| Name | Required | Description | Default |
|---|---|---|---|
| hetu | Yes | The Finnish HETU, e.g. 131052-308T (case-insensitive). |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the readOnlyHint annotation indicating a safe read operation, the description adds that it 'validates structure only,' setting expectations that it does not check identity existence or assignment. It also explains the structural components being validated.
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?
Two sentences, no wasted words. The imperative 'USE THIS' front-loads the purpose, and every sentence adds value without redundancy.
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?
Given the simple single-parameter schema and no output schema, the description fully covers the tool's behavior, limitations, and usage context. No gaps remain.
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 schema already provides a description with an example, but the description adds meaning by explaining the structure format (DDMMYY + century sign, etc.), which enriches understanding beyond the schema's brief description.
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 clearly states it validates a Finnish henkilötunnus (HETU), specifies the exact structure it checks (DDMMYY + century sign + individual number + mod-31 check character), and distinguishes itself from sibling validation tools by targeting a specific identifier format.
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 explicitly guides to use this tool to verify a HETU before relying on it and warns against guessing the check character. It provides clear context for when to use it, though it does not mention alternatives or when not to use it.
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 specific identifier or operation (e.g., validate_iban, parse_date, is_holiday). Even similar tools like validate_isbn and validate_isbn10 are distinct by version. There is no overlap or ambiguity.
Most tools follow a verb_noun pattern (validate_xxx, parse_xxx, format_currency). The exception is 'next_holiday', which uses an adjective instead of a verb. Otherwise consistent.
With 47 tools, the set is very large. While each tool is distinct, the count exceeds the recommended range (25+ is considered too many) and may overwhelm users or agents.
Covers a wide array of international identifiers and utilities, but notable gaps exist (e.g., no Canada SIN, India PAN, Mexico CURP). The set is broad but not exhaustive for the domain of data validation.