Get a database host

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

The annotations (readOnlyHint, destructiveHint) already indicate a safe read operation. The description adds behavioral detail by explaining that setting 'databases: true' changes the response to list databases instead of the host record. This exceeds the annotation baseline 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?

The description is two sentences, direct, and free of fluff. It states the core operation and the one key caveat about the 'databases' parameter. No unnecessary details or repetition.

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 simple get operation with no output schema, the description is complete. It tells the user exactly what to expect: either the host record or a database list when 'databases: true'. No additional context is needed.

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% with clear descriptions for all six parameters, including the 'databases' boolean. The tool description does not add significant extra meaning beyond the schema, but it reinforces the 'databases' parameter's role. This meets the baseline for fully documented parameters.

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 clearly states the primary action: 'Fetch one database host by UUID.' It also explains the alternative behavior with 'databases: true', making the tool's purpose unmistakable. The title 'Get a database host' reinforces this, and it is distinct from sibling list tools like 'list_database_hosts'.

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 implies the target use case: fetching a single record by UUID. It does not explicitly contrast with the list sibling, but the phrase 'by UUID' and the 'instead' for listing databases provide sufficient guidance. The behavior of setting 'databases: true' is also described, which helps users know when to use that feature.

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