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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is covered. The description adds non-annotation value: the required 'buildings:write' auth scope and the lat/long coupling and null-clearing behavior, which an agent cannot infer from annotations alone.

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 tight sentences, no filler, with the core operation front-loaded before the constraint details. Structure is efficient; slightly more could be trimmed but nothing is wasted.

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 10-parameter update with 100% schema coverage and no output schema, the description covers purpose, required scope, and the trickiest parameter interaction. It stops short of explaining partial-update behavior for the remaining optional fields, which would complete the picture.

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 coverage is 100%, so the baseline is 3, but the description adds a semantic rule not fully captured elsewhere: latitude/longitude must be sent together and both set to null to clear the position. It doesn't clarify whether omitting a field leaves it unchanged, which limits it to a 4.

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 ('Update an existing building by ID'), clearly distinct from siblings like create_building and delete_building. It does not explicitly name a sibling or scope what an update can do beyond ID lookup, but the operation is unambiguous.

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 implies when to use it (to modify an existing building) and states the 'buildings:write' prerequisite. However, it gives no explicit when-not guidance (e.g. preferring bulk_update for multiple buildings) or clarification of partial vs full update semantics, leaving context inferential.

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