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

No annotations provided, so description carries full burden. It discloses it's a server cache, metadata-only, and doesn't search YouTube. While read-only behavior is implied, explicit 'read-only' would improve. Still, it provides enough behavioral context for safe use.

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?

Three tightly-coupled sentences: purpose, limitations, and pointer to sibling. No fluff, front-loaded with main action, and every sentence adds value. Excellent structure.

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?

No output schema given, so description should cover return value. It states 'metadata only' but doesn't specify which metadata fields are returned. With 5 parameters and no output schema, this is a notable gap. However, the description is otherwise informative within its scope.

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 coverage is 60% with descriptions for some parameters. Description adds high-level filter categories (channel, date, transcript) but doesn't detail specific parameter formats or constraints beyond what schema already provides. Adds some context but not substantial new meaning.

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 Celestia-related YouTube videos from a cached server, with filters. It uses a specific verb 'Browse' and resource 'YouTube videos cached on this server', distinguishing it from siblings like 'get_video' and general YouTube search tools.

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?

Explicitly states when not to use: 'does NOT search YouTube at large' and directs to 'use a dedicated YouTube tool for that'. Also points to 'get_video' for transcript retrieval, providing clear alternatives.

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