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

Annotations declare a non-read-only, non-idempotent, non-destructive write but say nothing about workflow. The description adds genuinely new behavior: confirm=false previews, confirm=true applies, which is critical for a mutation tool. It stops short of permissions/rate-limit/error context.

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?

Four compact clauses, operation first, each parameter annotation in-line; zero filler sentences. The confirm semantics land last, which is the right place for a workflow note.

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?

Output schema exists so return values need not be explained, and the preview/apply contract covers the main safety concern. Gaps are the identity parameters (account_id/campaign_id/customer_id usage) and whether the adjustment is applied at campaign or ad-group level.

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 0%, so the description carries the burden and does partially compensate: it supplies the criterion_type domain (Age | Gender), a value format example (TwentyFiveToThirtyFour, Male | Female) and the unit for bid_multiplier (%). It says nothing about account_id, campaign_id or customer_id, leaving 4 of 7 parameters undocumented anywhere.

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?

Specific verb+resource: 'Adds a demographic bid adjustment' with the exact Microsoft surfaces it touches (Age | Gender criterion, bid multiplier). An agent can tell it apart from add_microsoft_device_target or add_microsoft_location_target by subject matter, but the description never explicitly names or contrasts a sibling.

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?

Usage is implied by the criterion/value enumeration rather than stated: no 'use this when' or 'prefer X instead' and no prerequisite (e.g. campaign must exist, account must be connected via connect_microsoft_ads). The confirm=false/true preview workflow is the only workflow guidance offered.

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