list_sources

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

With no annotations, the description must convey behavioral traits. It adds context by noting the 'RPC-only metadata path' and that the data is 'authoritative remote,' which suggests a specific access mechanism and data source. However, it does not disclose potential limitations, authentication requirements, or error behavior, leaving some gaps.

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 two sentences, front-loaded with the primary purpose and followed by a brief usage hint. Every word earns its place; there is no redundancy or irrelevant detail.

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 simple (one parameter, no output schema), and the description covers its core function, output content (source IDs and titles), and usage timing. However, it omits parameter format, authentication prerequisites, and error scenarios, which are relevant for a complete picture, though not critical for a simple read-only list tool.

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 has one required string parameter 'notebook' with no description and 0% schema coverage. The description says 'for one NotebookLM notebook,' which clarifies that the parameter refers to a notebook, but it does not explain that the value should be a notebook ID or how to obtain it. This is minimal additional meaning beyond 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 ('authoritative remote source IDs and titles for one NotebookLM notebook'). This is unambiguous and distinguishes it from sibling tools like list_notebooks, which list notebooks rather than 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 gives a clear usage context: 'Use before discussing corpus scope or freshness.' This tells the agent when to invoke the tool, but it does not mention alternatives or when not to use it, so it falls short of a 5.

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