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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint. Beyond those, the description discloses non-obvious behavior: unsupported or ambiguous endpoint slices return diagnostics without making an Amazon call, and AMC is excluded. That failure/no-op mode is genuine added value not present in the annotations or schema.

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?

Two sentences, zero waste, front-loaded with what is returned followed by scope exclusions. Appropriate size for a broad multi-endpoint tool without padding.

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, annotations, and full param coverage exist, so return-format and argument detail need not be repeated. The description adequately conveys scope and no-call behavior. Its one real gap is failing to position the tool against the overlapping get_sp_targeting_options and get_bid_recommendations siblings.

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 already carries the per-parameter semantics (including how profile_id resolves, which params are SP/SB/SD-specific, and pagination cursors). The description adds no per-parameter detail. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb (Return) and resource (targeting option and bid-recommendation fields) across the three Amazon ad products (SP, SB, SD), which implicitly distinguishes it from the SP-only get_sp_targeting_options and the get_bid_recommendations siblings. It stops short of naming those siblings explicitly, so the differentiation must be inferred by the agent.

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?

Gives some scope boundaries ("documented read-only endpoints", "AMC is out of scope", unsupported slices return diagnostics), which is implied usage guidance. However, with 39 parameters and a broad option_type enum, it never states when to choose this tool over the closely overlapping siblings get_sp_targeting_options or get_bid_recommendations.

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