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

Despite annotations already marking it read-only and idempotent, the description adds deep behavioral context: the meaning of 'restricted', the unfiltered nature of tool_count, how restricted:false is not a global all-clear, and the explicit warning not to compute or report differences with list_tools. It also discloses error behavior for unknown slugs.

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 long but every sentence earns its place by presenting a distinct fact or warning. It front-loads the core purpose, then builds context for restrictions, tool_count semantics, and error behavior without repetition.

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?

With no output schema, the description fully compensates by explaining what the object contains, how the restricted flag behaves, what tool_count means, and what happens on an unknown slug. The tool is simple enough that nothing needed for correct invocation or interpretation is omitted.

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 single parameter slug is already fully documented in the schema with an example and a note about never using a prefixed id. The description does not add meaning beyond referring to lookup 'by slug', so the schema carries the parameter burden and the baseline of 3 applies.

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 opens with a specific verb and resource: 'Read one connector definition by slug' and enumerates the returned fields. It explicitly distinguishes itself from connector.list_tools by stating this tool returns no tool schemas.

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 states when to use it ('Read it before anything else') and names the alternative for tool schemas ('use connector.list_tools'). It also explains the safety reason: connector.list_tools refuses blocked connectors outright, so this tool is the way to learn about that without provoking the refusal.

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