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

Annotations already establish this is a mutating, non-idempotent, non-destructive call, and the description adds the important behavioral caveat that no content sync happens on creation. It also discloses the return value, though it does not detail error/failure behavior; still, the key side-effect boundary is clear.

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?

Three tight sentences front-load the core purpose and immediately follow with the most important constraint and lifecycle caveat. There is no 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 tool with a massive settings schema and an output schema, the description is appropriately scoped: it covers purpose, the type/settings invariant, return behavior, and the sync boundary without duplicating schema details. The sibling pointer to run_data_source completes the lifecycle context an agent needs.

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 the schema does the heavy lifting; the description adds only the general constraint that 'settings' must match 'type'. That constraint is already present in the schema, so the narrative adds little parameter-level meaning.

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 names a specific action (create) and resource (data source), defines the scope ('for the authenticated application'), and clearly distinguishes itself from run_data_source by stating that creation does not sync content. This makes the tool's role unambiguous even among many create/list/update siblings.

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 explicitly states when to use this tool (create a new data source) and what it is not for ('does not sync any content'), then points to the exact alternative: 'use run_data_source to start a sync'. This is strong when/when-not guidance.

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