geoparquet_summarize_h3

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

With no annotations provided, the description carries the full behavioral burden and exceeds it: it discloses remote computation, bounded result size, bounding-box-center binning versus true geometry, DuckDB H3 extension dependency, and the explicit failure behavior if the extension cannot be loaded. This gives an agent strong insight into side effects and limitations.

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?

The description is structured into clear sections - usage, parameters, return values, and caveats - and every sentence adds information. Even the H3 extension note earns its place by preventing the agent from assuming a silent fallback exists.

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?

Despite the absence of annotations and schema-level parameter descriptions, the description fully equips an agent to select and invoke this tool correctly. It covers input semantics, output structure (cells, feature_count, centre, features_binned, truncated, scan), and edge-case behavior around resolution and extension loading.

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 fully compensate, and it does. Every parameter is explained: source, the four rectangle coordinates in WGS84 with requiredness, resolution with real-world scale examples and tuning guidance, limit with ordering semantics, and include_cell_centre with its plotting purpose.

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 opens with a specific verb and resource: "Bin the features inside a rectangle into H3 hexagonal cells and return the count per cell." It further distinguishes the tool by labeling it "A density map, computed remotely," separating it from sibling aggregation and filtering tools.

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 provides an explicit "WHEN TO USE IT" section with concrete queries like "where are these densest" and "how is this spread across the city," plus the heatmap heuristic. It does not explicitly name alternative sibling tools or state when not to use this tool, but the use cases and efficiency rationale are clear.

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