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

Beyond the annotations, the description discloses important mutation behavior: omitted fields keep their current values, changes apply within seconds, and removing or lowering access closes open connections. It also mentions the required permission scope, databases.write. These details are consistent with the destructive and idempotent annotations and add meaningful operational context.

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 compact and front-loaded, starting with what changes and then adding side effects and exclusions. Every clause carries actionable information, including the connection-closing warning and permission scope, with no redundant 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 destructive mutation tool with no output schema, the description covers the essential behavior an agent needs: partial-update semantics, timing, connection side effects, unsupported targets, and authorization scope. Nothing critical for safe invocation appears to be missing.

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 75%, so the schema already documents most parameters, including database and username. The description adds useful semantics for the optional fields: databases can be a list or null for all databases including future ones, read_only controls whether the user only reads, and an omitted field preserves its existing value. It does not add anything for database or username 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 states a specific verb and resource: it sets the logical databases a database user may connect to and whether that user is read-only. It also scopes the operation precisely by excluding the admin user and Valkey, so an agent can distinguish this from sibling database-user tools such as create_database_user or reset_database_password.

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 explicit exclusions: not for the admin user, which always has every database, and not for Valkey. It also warns to tell the user first when access is removed or lowered because open connections will be closed. It does not name a direct alternative sibling tool, so it falls short of the explicit when/when-not/alternatives standard for a 5.

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