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

Annotations already declare the tool as read-only, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds useful behavior beyond that: footprint coordinates are omitted and only their count is returned, avoiding a false expectation about payload contents. It says nothing about behavior for missing or unknown project_id/run_id or about release pinning semantics beyond 'pin the source release'.

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 with no filler, front-loaded with what is returned before the caveat about footprint coordinates and the run_id hint. The middle clause about browser/API/export availability is slightly roundabout but serves the error-avoidance goal.

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 two-parameter read-only lookup with an output schema, the description covers what the tool produces and how to scope the release. Re-enumerating the output fields is mildly redundant given the output schema, and error behavior remains undocumented, but nothing essential for invoking it 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 0%, so the description must carry the burden for both parameters. It explains run_id's provenance and purpose (take it from search to pin the release) but leaves project_id entirely unelaborated — no format, no source, no relationship to the 'merged project' that is returned.

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?

The description states a specific verb and resource ("Get one merged project") and enumerates what the merged record contains: observations, capacity evidence, timeline, matching evidence and conflicts. It does not explicitly contrast itself with siblings like get_parcel or get_state_summary, so the boundary between them is left implicit.

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?

There is one concrete usage instruction: pass run_id from search to pin the source release, which is genuinely actionable. However, there is no guidance on when to choose this tool over the other single-resource lookups or list/search tools, and no mention of what to do when run_id is unknown.

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