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 fully covered. The description adds only the filterable fields; it says nothing about result ordering, what happens with no filters, or that this returns assignments rather than locations themselves. Adequate but not rich.

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?

Two short sentences, zero filler, with the core purpose front-loaded before the filter note. It is efficient, though the second sentence is essentially a restatement of parameter names already visible in the schema, which costs a point.

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 full annotation coverage, a complete schema, and no output schema to explain, the description is just barely sufficient. It omits whether both filters can be used together and whether unfiltered calls return all assignments, which an agent would need to call it confidently.

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 every parameter already carries a description in the schema, so the schema does the heavy lifting. The description restates the two filter parameters ('by project_id or location_id') without adding meaning beyond the schema. Baseline 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 ('List') and resource ('location assignments for projects'), and the phrase 'assignments' distinguishes it from list_locations or get_project_location by implying a join/association between projects and locations. It does not explicitly name a sibling to route against, so it falls short of 5.

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 says what can be filtered ('by project_id or location_id'), which implies the two usage contexts, but it never states when to use this tool versus list_locations or list_project_sites, nor whether the filters can be combined. Usage is implied rather than guided.

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