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

Annotations already declare readOnly, idempotent, non-destructive behavior. The description adds valuable context about the change feed semantics: signed cursor for pagination and the types of changes tracked (added, changed, withdrawn, removed). This goes beyond the annotations and helps the agent understand the tool's behavior.

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 a single, well-structured sentence that front-loads the core purpose and lists the entity types and action types. Every word contributes meaning, with no redundancy or filler.

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?

The tool has an output schema, so return format is covered there. The description explains the change feed purpose, the types of changes, and the optional cursor for pagination. It sufficiently distinguishes from sibling tools, though it could optionally mention ordering or limitations, but these are not essential given the 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 coverage is 100% and the single optional cursor parameter is already fully described in the schema as an 'Opaque signed cursor returned by the previous change-feed page'. The description only mentions 'after an optional cursor', which adds minimal extra meaning beyond the schema's own description.

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The description uses specific verbs and resources: 'Track added, changed, withdrawn, and removed startup credits, discounts, free tiers, perks, and deals'. It clearly distinguishes this tool from siblings by specifying the change feed nature, which contrasts with search, compare, and inspect tools.

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 clearly implies use for tracking changes over time via the signed change feed, with an optional cursor for pagination. It does not explicitly state when not to use it or mention alternative tools, but the context is clear enough for an agent to decide when to invoke it.

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