Update Ad Source

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

Annotations already indicate a write operation (readOnlyHint false) and idempotency (idempotentHint true). The description adds the tag-based addressing constraint and clarifies the updateable flags, which is useful context beyond the annotations. It does not elaborate on side effects, error handling, or permission requirements, but this is acceptable given the simple update operation and annotation coverage.

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 with no filler. The first sentence front-loads the action and lists the changeable attributes; the second adds the essential addressing rule. Every clause provides value, achieving high conciseness and clear structure.

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 moderate-complexity tool with 7 parameters and no output schema, the description covers the primary purpose and the key addressing requirement. The schema supplies remaining parameter details, and annotations cover idempotency. The only minor gap is the lack of explicit mention that only provided fields are updated (partial update), but this is implied by the schema's optional fields.

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?

The schema covers all 7 parameters with 100% description coverage, including the @ prefix for tag. The description adds the critical clarification that sources are addressed by tag, not id, which is not explicitly stated in the schema and is essential for correct parameter usage. It also enumerates the fields in prose, reinforcing schema semantics.

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 tool's action ('Update an ad source') and enumerates the specific attributes that can be changed (name, category, goal, traffic source, organic/disregarded flags). It distinguishes the tool from sibling create_source and delete_source tools by emphasizing the update scope, and the tag-based addressing note reinforces its purpose.

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 provides important context that sources are addressed by tag rather than id, which guides correct invocation. However, it does not explicitly state when to use this tool versus alternatives like create_source or delete_source, nor does it mention any exclusions or prerequisites. The usage context is implied but not fully delineated.

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