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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely non-obvious behavioral context: the Documents context block already contains this list, making routine calls redundant. It stops short of describing pagination or return shape, but that is a modest gap given the annotation coverage.

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 sentences, no filler. The core action and filter scope are front-loaded, redundancy guidance follows, and the sibling pointer closes. Every sentence earns its place.

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 read-only list tool with no output schema, the description covers the action, the filter dimensions, the precondition (the data is likely already in context), and the route to the read tool. Nothing an agent needs to call this correctly 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% and each parameter is documented in the schema (including the instruction to call list_my_estates for the estate id). The description restates the filter semantics at a high level but adds no syntax or format detail beyond the schema, so the baseline of 3 applies.

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 estate's uploaded documents') plus the optional filter scope ('by asset or task'). It also explicitly contrasts itself with the sibling read_document, so an agent can separate listing from reading without opening either schema.

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 an explicit when-to-call condition ('only to refresh after an upload or to filter to a specific asset's or task's documents') and names the alternative tool for the adjacent need ('To read a document's contents, use read_document instead'). This is exactly the when/when-not/alternative structure the top tier requires.

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