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

Goes well beyond the annotations, which only declare a safe read. It discloses auth requirements ('Requires connecting a Valet account'), partial-failure semantics ('A connector that could not be reached reports its own error and leaves every other row intact'), and session semantics the consumer must be aware of (initialize handshake, Mcp-Session-Id replay, re-initialization).

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?

Four paragraphs, front-loaded with the core purpose and value. The MCP session/framing material is dense but relevant to the stated use case of writing a page, though some of it ('the broker forwards the handshake and the tool calls') sits close to the edge of what a caller needs.

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 carries the full burden and does it well: it explains what each row contains (connectors and their callable tools), callability and session indicators, and error behavior. Nothing essential to calling or interpreting the tool is missing.

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 100%, so the schema already documents name, org_name, and connector. The description's 'Pass connector to read one' merely restates the schema's 'to read only that one,' adding no new syntax or format detail. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

States a specific verb and resource ('List the connectors attached to a website, each with the tools a page served from that site can call'). It explicitly differentiates from siblings like list_connectors ('what the organization has available') and get_service ('for an app or agent'), so an agent can route correctly without opening either schema.

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?

Gives explicit when-to-use ('Read it before writing a page that calls one: the tool names and argument schemas it returns are what the page's own calls have to match'). It also names the alternative for other cases ('for an app or agent, get_service reports what is attached') and the condition for reading a single connector ('Pass connector to read one').

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