Update DNS Record

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

The annotations only provide readOnlyHint: false, which tells the agent this is a mutation but little else. The description adds meaningful behavioral detail: it updates an existing record (implies existence requirement) and supports partial updates (fields not provided remain unchanged). This goes beyond the sparse annotation without contradicting it.

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 sentences, front-loaded with the action ('Update an existing DNS record'), followed by a prerequisite and usage tip. No filler, every sentence earns its place.

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 an update tool with 9 parameters (2 required) and a fully descriptive schema, the description covers the key context: partial update behavior and how to obtain the record ID. With no output schema, return values are not required to be explained. It is sufficiently complete for the tool's complexity.

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?

The input schema has 100% coverage with descriptions for every parameter, so the baseline is 3. The description adds a general note about partial updates ('Only provide the fields you want to change') which clarifies parameter optionality, but it does not add per-parameter meaning beyond the schema.

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 uses a specific verb and resource: 'Update an existing DNS record.' It clearly distinguishes from siblings like create_dns_record and delete_dns_record by emphasizing 'existing' and 'update.'

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 clear usage context: 'Only provide the fields you want to change' explains partial update semantics, and 'Use list_dns_records first to find the record ID' gives a concrete prerequisite and points to a sibling tool. However, it does not explicitly mention when not to use this tool or name alternatives for other operations.

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