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

With no annotations provided, the description carries the transparency burden. It discloses access requirements ('free, no key'), implies a read-only lookup operation, and describes the output in terms of confirming hash validation and timestamps. This is strong behavioral context for a simple retrieval tool.

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, tight sentence followed by a short clarifying clause. Every element adds value—what it does, the identifier format, access requirements, and expected output. There is no redundancy or filler.

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 tool with one simple parameter and no output schema, the description covers the essential behaviors: what to look up, that no authentication is needed, and what the result conveys. It does not explain edge cases like expired or missing certificates, but the low complexity makes the current description reasonably complete.

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 only provides the parameter name 'cert_id', so the description must compensate. It adds the EIW-… format hint, which helps the agent understand the expected value, but it does not explicitly explain where the cert_id comes from or how to format it. This is partial compensation rather than full parameter documentation.

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 specific action ('Look up a verification certificate'), identifies the resource type by its EIW-… prefix, and explains the value ('Confirms which file hashes passed validation and when'). This clearly distinguishes it from validation and creation tools like validate_einvoice and create_facturx_pdf.

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 clear context: this is a lookup, not a validation or creation operation, and it explicitly notes that no key is required. It does not name sibling alternatives or state when not to use it, but the intended use case is clear enough for an agent to select it appropriately.

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