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

Annotations only declare safety flags, so the description carries the burden of behavior. It discloses that assignment may create the physical database and start synchronization automatically, revokes the old host's minted credential on host move, and does not evict existing manual pairings. This is rich, non-obvious context beyond the annotations.

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 front-loaded with the core operation and each subsequent sentence adds meaningful behavioral or prerequisite detail. It is dense but not bloated, and the doc link provides optional depth without cluttering the main guidance.

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 mutating tool with an output schema, the description covers prerequisites, side effects, parameter sourcing, and gotchas like credential revocation and manual pairing preservation. Nothing critical is missing for an agent to invoke this tool correctly.

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?

Input schema coverage is 100%, so the schema already documents both parameters. The description adds some nuance by explaining null means unassign and naming candidate sources, but most parameter meaning is already present in 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 pair, 'Assign or clear,' and names the exact resource, 'the host provisioning a database sync.' It clearly distinguishes this from related tools like create_database_sync and list_database_syncs by specifying that candidates come from those tools.

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?

Provides explicit prerequisites (owner, sync-enabled plan), parameter semantics (null to unassign), and candidate sourcing from create_database_sync or list_database_syncs. It does not fully enumerate when to avoid this tool versus sibling assignment alternatives, but the guidance is otherwise clear and actionable.

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