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

Goes far beyond the annotations by disclosing the re-validation of the address on every request, the idempotent behaviour ('adding the same address again returns the same connector'), and the failure taxonomy with literal codes (sign_in_not_open, sign_in_on_another_domain, sign_in_owner_unverified). It also states the credential constraint ('never ask for a key, a token or a password') and that an api_key is added outside the conversation, which is exactly the kind of operational context annotations cannot convey.

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?

Long but front-loaded: identity of the connector, then preconditions, then server-side checks, then outcome handling. Nearly every sentence carries an operational rule, though the outcome-by-outcome reply script makes it heavier than strictly needed for tool selection.

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?

For a write tool with open-world network access and multiple failure modes, the description covers permissions, pre-checks, idempotency, partial-success states and refusal wording. Even though an output schema exists (so outcome fields needn't be re-explained), the outcome-handling guidance adds useful agent behaviour rather than duplicating structure.

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 description coverage is 100% and each parameter already carries detailed prose, so the schema does the heavy lifting. The description only reinforces that url and name come verbatim from the person and that no credential parameter exists; it adds little per-parameter meaning beyond that. Baseline 3 is appropriate.

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, resource and scope: 'Save the MCP server of a tool Well's catalog does not carry as a connector of this workspace.' It immediately distinguishes itself from catalog-based siblings (well_request_connector, well_show_connector_request, well_update_custom_connector) by both what it creates and who sees it.

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 preconditions and the exact predecessor tools with their required return values ('only when well_show_connector_request returned can_add_self: true', 'after well_probe_mcp_server answered mcp_server'), plus the authorization gate (owner or admin, others refused). An agent knows precisely when to call it and when not to.

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