list_sources

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

No annotations are provided, so the description carries the burden. It discloses the result shape (list of sources with data types) and implies a read-only listing operation, but it does not add details about authentication, pagination, or any constraints. This is adequate but minimal for a zero-parameter listing 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?

A single sentence with no wasted words: it states the action, the scope, and the included detail. The key purpose is front-loaded and every word earns its 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 zero-parameter enumeration tool with an output schema, the description is complete: an agent knows exactly what the tool returns and how it fits into the server's search workflow. No additional context is needed to invoke 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 tool has zero parameters, so the description cannot add parameter-level information. The baseline of 4 applies because parameter semantics are not applicable and nothing about parameters is missing.

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 names a specific verb ('List'), a specific resource ('data sources this server can search'), and the key content ('data types each covers'). This clearly differentiates it from sibling tools like search_datasets and get_dataset, which operate on individual datasets rather than enumerating available sources.

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 clearly implies the tool is for discovering which data sources are searchable before using search_datasets or get_dataset. It provides clear context on what the tool returns, though it does not explicitly state when not to use it or name alternatives directly.

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