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

Annotations already mark the operation as non-readonly, non-destructive, and idempotent. The description adds the key behavioral trait that only provided fields change (partial update), which prevents agents from constructing full replacement payloads, and it states the return value. This goes beyond annotations, though it does not discuss side effects like re-syncs.

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 short, front-loaded sentences with the core action first and no redundant or promotional language. 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?

Given the complex settings oneOf and existing schema descriptions, the description captures the essential partial-update contract and return value. It does not repeat schema-level constraints like the type discriminator or WordPress integration_id requirement, which are already covered in the input schema and output schema.

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 67%, and the description supplements this with partial-update semantics: only provided fields are updated, implying optional parameters can be omitted and null can be used to clear values. It does not detail the settings variants, but those are already described 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?

States a specific action ('Update'), a specific resource ('data source'), and a scoping criterion ('by its ID'). The partial update note further distinguishes this from full-replace operations and from sibling update tools like update_node, update_prompt, and update_tool.

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 clear context: this tool performs partial updates on an existing data source identified by UUID, so an agent knows to omit unchanged fields. However, it does not explicitly state when not to use it or name alternative data-source operations, so it stops short of full 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.