youtube_auth

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

No annotations are provided, so the description carries the full burden. It discloses that a browser window opens (user-facing behavior) and that it's a prerequisite step, but doesn't mention that this is a blocking/awaiting-user action, how long the flow may take, whether it's non-reversible, or what success/failure looks like. The description adds value but leaves gaps about the interactive nature.

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 appropriately brief at two short paragraphs. It front-loads the core purpose in the first line and adds the prerequisite context in the second sentence. Minor spacing waste with the blank line, but otherwise efficient.

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?

This is a simple 0-param tool, so a short description is acceptable. However, given it's an authentication flow likely requiring user interaction in a browser, the description could mention the interactive/blocking nature and what happens on success or failure (e.g., a token is stored for subsequent calls). The return behavior is unspecified but no output schema exists to compensate.

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?

There are 0 parameters and schema description coverage is 100% (vacuously, as there are no properties). With 0 params, the baseline is 4. The description appropriately doesn't attempt to document nonexistent parameters.

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 states 'Initiate OAuth 2.0 authentication flow' which is a specific verb+action, and clarifies it opens a browser window for Google OAuth consent. It's clear what the tool does, though it doesn't explicitly differentiate from youtube_auth_status, which is the nearest sibling representing the status check of this flow.

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 states 'Required before using any tools that access private channel data or analytics,' providing explicit when-to-use context. It doesn't mention exclusions or alternatives, but does clarify the prerequisite nature clearly enough to guide usage.

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