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

readOnlyHint=true already tells the agent this is a safe read, so the description's remaining burden is light. It adds two useful facts beyond annotations — that results are paginated and that the underlying call is GET /estimates — but says nothing about return shape, page-size ceilings, or rate limits.

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?

Three compact fragments, no filler: purpose and filters first, then pagination, then the REST mapping. Every clause carries information and the scoping details are front-loaded.

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-required-parameter read-only list tool with a fully documented schema and readOnlyHint covering safety, this is nearly sufficient; the pagination note is the one piece of context the schema cannot convey. Output schema absence is expected for a list endpoint, so nothing critical is missing.

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 every parameter including formats (yyyy-mm-dd, ISO-8601), enum values, and page bounds is already documented in the schema. The description restates the same filter set without adding syntax or semantics beyond it, which is the baseline for this case.

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 ('List') and resource ('estimates') and enumerates the filter dimensions, so the agent knows exactly what comes back. The resource itself distinguishes it from sibling list tools like harvest_list_invoices or harvest_list_expenses, though the description never explicitly says so.

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 filter list implies when the tool is appropriate (broad listing with optional narrowing), but there is no explicit when-to-use guidance and no stated exclusions or alternative tool to prefer. Usage is inferable rather than directed.

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