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

With no annotations, the description carries the full burden. It usefully discloses that the call returns the DNS record to create, which hints it is a configuration step rather than a completed state change. It omits whether the operation is idempotent, what happens on re-connect, permission requirements, and whether DNS ownership is validated.

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 compact sentences with zero waste; the core mapping action is front-loaded, followed by the practical next step. Nothing superfluous is included.

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?

No output schema exists and the description partially compensates by noting the returned DNS record to create. For a mutation tool with three required params and no annotations, though, missing prerequisites, idempotency, and failure behavior leave real 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 description coverage is 100%, so env/host/project are already documented in the schema, and the description adds no field-level syntax or format guidance. Baseline 3 is appropriate when the schema does the work and the description only echoes the concepts.

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 with scope: "Map a domain you own to an environment." The phrase "a domain you own" implicitly separates it from domains.buy/domains.search, though no sibling is named outright. An agent can tell what it does without opening the 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?

It gives the post-call instruction ("Point its DNS at the Plinth host"), which implies the usage flow after invocation. However, it never states when to use this versus domains.verify or domains.list, nor the prerequisite that the domain likely must already be purchased/verified before connecting.

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