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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds context about the returned fields and ordering, and the note about navigation-pointer vs project_id is a behavioral nuance not captured by annotations. However, it does not mention potential result size limits or pagination, which is a minor gap for a list operation.

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 with zero waste. The main action and ordering are front-loaded, and the critical note about navigation-pointer and project_id is delivered concisely. Every sentence 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 read-only list tool with no parameters and no output schema, the description provides the essential details: what is listed, the fields, ordering, and the relationship to project_id usage. It could mention whether there is a limit on the number of projects returned or how to handle pagination, but given the tool's simplicity and the annotations covering safety, it is largely complete.

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 schema coverage is trivially 100% and there is nothing to explain about parameters. The description focuses on output, which is not parameter semantics. The baseline for 0 params is 4, and the description adds value by clarifying the output fields, but that's beyond parameter semantics.

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 lists video projects with specific attributes (has video, kind, podcast-shorts status, parent) and orders them newest first. It distinguishes itself as the starting point for project discovery, which is a clear purpose that differentiates it from the many sibling tools that operate on a single project.

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 phrase 'Start here' explicitly instructs when to use this tool. It also clarifies that the navigation-pointer label is informational only and that other calls require project_id, providing guidance on how to use this tool's output to proceed with other tools. This is explicit usage direction.

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