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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and a closed world, so the safety profile is fully covered. The description adds only the scoping behavior of the site filter and says nothing about result volume, pagination, or how the automatic all-pages fetch behaves, so it is a modest addition rather than a rich disclosure.

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, front-loaded with the tool's action and followed by the one relevant filter option. There is no boilerplate and nothing extraneous; each clause carries information.

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 low-complexity, zero-required-parameter list tool with full annotation and schema coverage, this is nearly complete. The absence of any note on return shape is acceptable because no output schema exists but the tool is a simple enumerator; a mention of result scale would be the only missing piece.

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 page, per_page, search and site_id are already documented in the schema. The description echoes only the site_id filter and adds no format, default, or interaction detail beyond it, so the 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?

Clear verb+resource ("List buildings") and it is the only building-listing tool among the siblings, so there is little risk of confusion with create_building or list_building_types. However, it never explicitly distinguishes itself from neighboring list tools such as list_project_buildings or list_sites, so the sibling differentiation is implied rather than stated.

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?

"Optionally filter by site to see all buildings at a specific location" gives implied usage for the site_id case, but there is no guidance on when to prefer this over list_project_buildings or get_site, and no exclusions or prerequisites. Adequate but with a clear gap.

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