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

Annotations cover the safety profile (readOnly=false, idempotent=false, destructive=false), and the description adds two genuinely useful behavioral facts: the raw key is shown only once and per-plan key limits (3 Essential / 10 Pro). It does not cover what happens on duplicate names or whether the quota is per-account or per-workspace, so it falls short of exhaustive.

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 short sentences, each carrying distinct information (what it creates, the one-time return, the quota). The most decision-relevant facts are front-loaded with zero 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?

For a one-parameter creation tool with no output schema, the description covers the key behaviors an agent needs: the returned value is ephemeral and quota limits exist. Auth requirements and the omission/default behavior of 'name' are the only notable gaps.

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% for the single 'name' parameter, so the schema already documents it fully. The description adds nothing about the name parameter (uniqueness, defaults when omitted, required-ness), so the baseline 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?

States a specific verb (Create) and resource (REST API key) plus scope ('for /api endpoints') and the key prefix format ('mon_…'). This implicitly separates it from the sibling create_mcp_key, so an agent can route 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?

The '/api endpoints' qualifier implies the usage context, but the description never explicitly says when to choose this over create_mcp_key, nor any prerequisite (e.g., plan, permissions, whether existing keys block creation). Usage is inferable but not stated.

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