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

Annotations already declare the tool read-only, idempotent, non-destructive, and not open-world, so the safety profile is covered. The description adds useful context by naming the GLEIF API source and stating no API key is required, plus what fields are returned, though it does not discuss error or rate-limit 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?

The description is front-loaded with the core action and return fields, followed by a compact when-to-use list. Every sentence supports selection or invocation, with no 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?

The tool is a read-only detail lookup with rich annotations and an output schema, and the description covers the key input and returned fields well. Completeness is slightly reduced because the unrelated optional schema parameters are left unexplained, which could confuse an agent inspecting the full input schema.

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 description identifies the core input as a 20-character LEI code and points to SearchLEI as the source, which matches the key schema field. However, the schema exposes several internal/optional parameters such as mcp_prompt_id, wholesaler_ids, and source_resource_id that the description does not address, so it only partially compensates for low schema coverage.

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 starts with a specific verb and resource: retrieve the full GLEIF LEI record for one legal entity using a 20-character LEI code. It lists the returned fields and clearly distinguishes this from SearchLEI by requiring an already-known LEI for full details.

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?

It provides an explicit 'Use this tool when' section with concrete conditions: you already have an LEI from SearchLEI, need registration status, or need the exact legal address and jurisdiction. This gives the agent clear routing guidance against the sibling lookup tool.

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