NotebookLM MCP Server (Security Hardened)

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

Annotations provide hints (readOnlyHint=false, destructiveHint=false, idempotentHint=true, openWorldHint=true), but the description adds valuable context by listing source types (url, text, file) with examples, clarifying what can be added. It does not contradict annotations—'Add' aligns with non-readOnly and non-destructive hints—and supplements with practical behavioral details not covered by 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?

The description is front-loaded with the core purpose, followed by a structured list of source types and a clear JSON example. Every sentence earns its place by providing essential information without redundancy, making it efficient and easy to scan for key details.

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?

Given the tool's moderate complexity (3 parameters, nested objects, no output schema) and rich annotations, the description is largely complete. It covers purpose, source types, and usage example, but lacks details on error handling, response format, or prerequisites (e.g., authentication), which could enhance completeness for a mutation 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?

Schema description coverage is 67%, with parameters like 'notebook_id' and 'source.type' well-described in the schema. The description compensates by detailing source types (url, text, file) and providing an example that illustrates parameter usage and structure, adding meaning beyond the schema's enum and object definitions, though it doesn't cover all parameters exhaustively.

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 specific action ('Add a source') and resource ('to an existing NotebookLM notebook'), distinguishing it from sibling tools like 'add_notebook' or 'create_notebook' which create notebooks rather than adding sources to existing ones. The verb 'Add' is precise and the scope 'existing NotebookLM notebook' sets clear boundaries.

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 implies usage context by specifying 'to an existing NotebookLM notebook,' which suggests it should not be used for creating new notebooks (use 'add_notebook' or 'create_notebook' instead). However, it lacks explicit when-not-to-use guidance or named alternatives for source management (e.g., vs. 'remove_source' or 'list_sources'), leaving some ambiguity in sibling differentiation.

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