gleif-mcp-server

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

Annotations already indicate read-only and idempotent behavior, but the description adds valuable context: it specifies that the tool lists entities (not modifies them), clarifies failure conditions for invalid inputs, and implies it returns a list of results. However, it doesn't detail pagination, rate limits, or authentication needs beyond what annotations provide.

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 purpose, followed by structured usage and failure guidance. Every sentence adds value: the first states what it does, the second provides usage examples, and the third clarifies input requirements. No wasted words or redundant information.

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 read-only tool with good annotations and full schema coverage, the description is nearly complete. It covers purpose, usage, and input constraints effectively. However, without an output schema, it could briefly mention the type of results returned (e.g., 'list of entities with basic details') to fully compensate.

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 100%, so the schema fully documents parameters (country as ISO code, limit with default). The description adds minimal semantics by reinforcing the country code format and providing usage examples, but doesn't explain parameter interactions or edge cases beyond what's in the schema.

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's purpose with a specific verb ('List') and resource ('entities registered in a specific country'), distinguishing it from siblings like 'search_by_bic' or 'search_by_isin' that filter by different criteria. It explicitly mentions the type of entities (companies, LEIs) and the filtering mechanism (by country).

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 usage guidance with 'USE WHEN' examples (e.g., 'companies in Germany', 'LEIs from US') and 'FAILS WHEN' conditions (e.g., incorrect country code formats). It distinguishes this tool from alternatives by focusing on country-based filtering, unlike siblings that search by BIC, ISIN, or entity name.

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