source_list

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

Annotations already provide readOnlyHint, idempotentHint, and openWorldHint. The description adds a practical behavior detail—'RPC-backed (no browser)'—which helps set execution expectations without contradicting the 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?

Two short sentences capture the functionality, the return value purpose, and a relevant execution detail. There is no filler, and the core use case is front-loaded.

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 has a complete input schema, annotations, and an output schema. The description additionally explains why an agent would call it and what downstream tools need its result, making it fully self-contained for selection and 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 100%, so the input schema already documents both notebook_id and notebook_url. The description adds no extra parameter-level meaning beyond pointing at the source_id output, so a baseline score per schema coverage is appropriate.

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 action ('List the sources of a NotebookLM notebook') and what is returned (IDs and titles). It also ties the output to downstream consumers (read_source and delete_source), making the tool's role unambiguous among many siblings.

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 explicitly states when to use this tool: to get the source_id that read_source and delete_source expect. It does not enumerate when not to use it or mention alternatives, but the primary use case is clear enough for an agent to select it over other source-related tools.

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