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

No annotations are provided, so the description carries full burden. It discloses that the tool returns 'the complete surface in a single response,' but does not mention side effects, authentication, rate limits, or output structure. For a read-only directory, this is adequate but lacks depth.

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 consists of two sentences, both of which earn their place. It front-loads the purpose ('Master directory...') and immediately follows with usage guidance ('recommended first call'), with zero wasted words.

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 simplicity (0 parameters, no output schema), the description covers the key aspects: what it returns, what it includes, and how it fits into the broader toolset. It could be more specific about response format, but it is sufficient for this complexity.

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 (empty schema), so the baseline score is 4 per the rubric. The description adds context about the tool's scope, but no parameter-specific details are needed since there are none.

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 identifies the tool as a master directory of all MegaChad endpoints, MCP tools, manifest URLs, and examples. This specific verb+resource combination distinguishes it from the many other get_* sibling tools, which target individual resources.

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 'The recommended first call for any agent,' providing clear context on when to use this tool. It does not explicitly mention alternatives or exclusions, but the guidance is sufficient for a directory tool.

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