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

Annotations declare readOnlyHint=false, idempotentHint=false, destructiveHint=false. The description adds valuable context beyond annotations: the review-before-publication delay, error handling semantics, and the explicit prohibition on secret values. It does not contradict annotations and enriches the agent's understanding of the tool's behavior.

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?

Three sentences, each carrying distinct and essential information: purpose, review/status behavior, and error-handling/security guidance. The description is front-loaded with the core action and remains tightly structured with no filler.

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 complexity (14 parameters, mutating action, no output schema), the description covers the critical behavioral context: the review workflow, error retry, and secret handling. It doesn't explain return values, but no output schema exists, so this is a minor gap. Overall, an agent has enough to invoke it correctly.

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%, so each parameter is already well-documented. The description reinforces the env_vars rule ('names only, not values') and gives general guidance on sourcing values, but adds little that isn't in the schema. Baseline 3 is appropriate; it adds marginal value but doesn't compensate for anything missing.

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: 'Add an MCP server to the registry.' It clearly distinguishes from siblings by referencing get_server for status checking, and the purpose is unmistakable. An agent can tell this is the creation/registration tool.

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 provides explicit usage guidance: what to fill (from README/metadata), what to do on error (fix fields and retry), and a security constraint (env_vars names only). It also explains the post-submission review process and how to check status via get_server, covering both when and how to use it effectively.

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