update_sd_ad_group_bid

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

With no annotations, the description carries full burden. It discloses the tool as a 'guarded write' that can preview updates, and reveals it is a stub on the local server. This adds valuable context about safety and availability, though it does not detail authentication needs or rate limits.

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 concise sentences, each adding unique value: the first states purpose, the second provides critical deployment context. No unnecessary words or redundancy.

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?

Despite having no output schema and 5 parameters, the description does not clarify what preview returns, which parameters are required for update vs preview, or the tool's full behavior. The stub status is noted, but essential operational details are missing, leaving the agent underinformed.

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 100%, so parameters are already well-documented. The description adds no additional meaning beyond the schema; it only reiterates the tool's purpose. Baseline 3 is appropriate as the description does not compensate for any existing gaps.

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 explicitly states 'Preview or update Sponsored Display ad group default bids,' clearly identifying the verb (preview/update) and resource (SD ad group default bids). It distinguishes from siblings like 'update_adgroup_bid' (likely for SP) and 'update_sd_target_bids' (for targets).

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 notes 'Hosted endpoint only; this local stdio server is an introspection stub,' advising that the tool is not fully functional locally. However, it does not provide guidance on when to use this tool versus alternatives like 'update_adgroup_bid' or 'update_sd_ad_group_state,' limiting its helpfulness for tool selection.

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