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

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), but the description adds genuinely new behavioral facts: the URL is SSRF-validated and authValue is encrypted at rest. It stops short of stating failure modes (e.g. duplicate name collisions) or whether a connection test is triggered.

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?

Two short sentences, zero filler, with the core action front-loaded and the security caveat second. Nothing to trim.

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 10-parameter creation tool with conditional auth fields and no output schema, the description leaves the auth-parameter combinations, the allow-list behavior, and the identity of the created resource unexplained. It is minimally viable given annotations cover the safety profile.

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 only 50% across 10 parameters (enabled, authType, transport, description, displayName are undocumented in the schema), so the description carries a heavier burden — yet it adds nothing about parameters beyond echoing that authValue is encrypted, which the schema already states. No guidance on how authType, headerName and authValue interact, or on selectedTools semantics.

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: 'Register a new external MCP upstream server for the org.' The create/update/delete family is inferable from the name and sibling list, but the description itself never contrasts this with update_mcp_server or test_mcp_server_connection.

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?

No when-to-use guidance, no prerequisites, and no routing to alternatives such as update_mcp_server (for existing servers) or test_mcp_server_connection (to verify one). The agent must infer everything from the name.

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