list_spis_use_case_ids

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

With no annotations, the description carries the behavioral disclosure burden. It usefully exposes a required environment variable and the authoritative data source, which are not visible elsewhere. It does not spell out the failure mode if the directory is missing, but the operation is a low-risk list and the name implies read-only 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?

Two sentences, no filler. The first sentence states the core purpose immediately; the second sentence provides a necessary operational prerequisite. Both sentences earn their 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 simple one-parameter list tool with an output schema available, the description is nearly complete: it names the source, states the environment dependency, and routes the agent to a sibling for the directory context. It could add a note about read-only side effects, but nothing critical is missing for calling it 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?

The only parameter, active_only, is fully documented in the schema including its default and meaning, so the description does not need to repeat it. The tool description adds no parameter-level information, and with 100% schema coverage 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 first sentence states a specific action ('List'), a specific resource ('Peppol SPIS use case identifiers'), and the source list ('OpenPeppol eDEC code list'). It is easily distinguished from sibling tools like list_document_type_ids and list_process_ids because it names a different kind of identifier.

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 a clear prerequisite by requiring EINVOICING_PEPOL_CODELIST_DIR and points to a related sibling for context. However, it never explicitly states when to choose this tool over the other list_* siblings 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.