check_participant_id_scheme_in_codelist

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

With no annotations provided, the description carries the full burden and does add one key behavioral fact: the tool depends on EINVOICING_PEPPOL_CODELIST_DIR being set. It also implies a non-destructive verification operation consistent with the 'check' semantics. It does not disclose failure behavior (e.g., missing env var, malformed input) or caching, though the output schema covers the return shape.

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 totaling roughly 25 words, with the purpose front-loaded in the first sentence and the prerequisite in the second. There is no redundancy or filler; every phrase earns its place.

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 single-parameter check tool with an output schema and no annotations, the description covers the purpose, the input format, and the one environmental dependency, and it routes the agent to a sibling for the full list. The only omissions — error behavior and explicit return phrasing — are minor because the output schema already exists.

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 0%, so the description must compensate for the undocumented `icd` parameter — and it does: '4-digit ISO 6523 ICD code' specifies format and digit count, and the example '0208' clarifies the leading-zero convention. This fully covers the single parameter's semantics; only marginal details like exact matching behavior are omitted.

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 predicate ('Check whether'), a precise resource (4-digit ISO 6523 ICD code), and a concrete example ('0208') to identify the subject as a recognized Peppol scheme. This clearly differentiates it from the sibling codelist checks (check_document_type_id_in_codelist, check_process_id_in_codelist) by naming the exact code type being validated.

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 states a prerequisite ('Requires EINVOICING_PEPPOL_CODELIST_DIR') and references list_participant_id_schemes for context, which gives useful operational guidance. However, it never explicitly says when to use this tool over the sibling codelist checks or gives when-not-to-use conditions; usage context must be inferred from the name and subject matter.

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