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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds valuable context beyond annotations by stating the source is the GLEIF API and that no API key is required, which are operational details an agent needs to know. It does not contradict annotations.

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 concise and well-structured. It front-loads the core purpose, lists the returned data, then provides clear 'Use this tool when' bullets, and ends with source and authentication info. Every sentence adds value with no 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?

While the tool has an output schema (so return values need not be described), the description does not adequately address the parameter landscape. It provides clear usage scenarios and source info, but leaves the many optional parameters unexplained, which could confuse an agent about whether to include them. Given the schema complexity (multiple optional params), the description is not fully complete for correct invocation.

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% per context signals, so the description must compensate for parameter guidance. It mentions the primary parameter (lei) with an example but completely ignores the other six parameters in the schema (mcp_prompt_id, question_asked, wholesaler_ids, exclude_fillers, source_resource_id, additional_display_fields, optional_additional_filters), many of which appear generic and irrelevant to this LEI lookup. The description does not clarify that only lei is needed and the rest are optional and likely unnecessary, leaving the agent unsure about what to pass.

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 the tool retrieves the full GLEIF LEI record for one legal entity using a 20-character LEI code, and lists the specific data returned (legal name, status, addresses, LOU, renewal dates). It also distinguishes itself from sibling SearchLEI by explicitly referencing obtaining the LEI from SearchLEI, making its purpose unambiguous.

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 provides explicit 'Use this tool when:' conditions, such as having a LEI from SearchLEI, verifying registration status, or needing legal address/jurisdiction. This clearly guides when to use this tool versus searching or other alternatives, and it implies SearchLEI is the preceding search tool.

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