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

Annotations already establish readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered; the description reinforces 'Read-only' and adds real context beyond that — workspace scoping, sort order, exclusion of line items, and pagination via has_more. It doesn't disclose defaults for limit/offset or a maximum page size (that lives only in the 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?

Front-loads the core behavior, then the read-only guarantee, then filters, then pagination and return shape — a logical progression where each clause adds information. No redundant restatement of the tool name or title.

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?

With seven parameters, zero schema descriptions, and no output schema, the description nonetheless covers filtering formats, paging, sort order, scoping, and an inline return shape of {items,total,has_more}. That is enough for an agent to invoke it correctly without further documentation.

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 must carry the parameter burden, and it largely does: date format YYYY-MM-DD for from/to, case-insensitive matching for merchant, allowed status values, and the limit/offset paging pair. Gaps remain — 'category' is listed with no matching semantics, and no default values are stated for limit/offset.

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 and resource ('List the caller's receipt headers'), plus scope qualifiers that matter: caller-owned, active workspace only, headers without line items, sorted newest date first. An agent immediately knows what comes back and in what order, distinct from any sibling listing tool.

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 parenthetical '(no line items)' implicitly routes an agent needing detail elsewhere, and the enumerated optional filters tell the agent how to narrow results. It stops short of explicitly naming an alternative tool for full receipt contents or stating when a filtered call is preferable to an unfiltered one.

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