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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, covering the safety profile. The description adds the 'all available' scope constraint, but says nothing about ordering, pagination, or potential incompleteness despite the open-world hint. This is acceptable but minimal additional transparency beyond the annotations.

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 entire description is a single six-word sentence that front-loads the action and result. Every word earns its place; there is no fluff, repetition, or unnecessary context. This is model clarity through brevity.

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 zero-parameter tool whose annotations cover safety and whose siblings provide contrasting context, the description is sufficient for correct invocation. No output schema exists, but the return type ('categories') is self-evident from the description. An agent needs nothing else to call this tool appropriately.

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 tool has zero parameters and the schema coverage is effectively 100% (empty schema). With no parameters to document, the description does not need to compensate for any schema gaps. Baseline for zero-parameter tools is 4, and nothing here lowers it.

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 a specific verb ('Get') and resource ('all available deal categories'), exactly matching the tool name's intent. It is clearly distinct from the deal-querying sibling tools, none of which address categories. No ambiguity remains about what the tool does.

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 states the tool returns all available deal categories, which clearly implies use when an agent needs the category list before filtering deals. It does not explicitly name alternatives, but the sibling set is entirely deal-focused, so the choice is unambiguous. This is clear context without needing formal exclusions.

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