List a project's input layers

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

Annotations already declare readOnly/idempotent/non-destructive, so the description's real value is the semantics it adds: null in has_features means unknown rather than empty, and a row without gn_layer means no layer yet. That is genuinely non-obvious behavior not recoverable from annotations or schema. It omits any statement about result size or pagination, keeping it below 5.

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?

Front-loaded summary sentence followed by a structured per-field breakdown; the parenthetical glosses for gn_layer and dataset_alternate earn their space. Slightly dense, with the one-line-per-kind framing doing most of the work, but there is no filler.

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?

An output schema exists, so return shape needn't be spelled out — yet the description covers the interpretive edge cases (null vs. empty, missing gn_layer) and the intended downstream use with create_scenario. Nothing an agent needs to select and call this 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?

There is a single parameter with 100% schema coverage, so the schema already defines project_id. The description adds nothing about the parameter itself (e.g. what happens with an unknown or empty project), 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?

States a specific verb and resource ('List every input layer row of a project') plus the exact scope: per kind, with has_features. The enumeration of kinds (boundary, friction, inflow, rainfall, building, mesh_region, culvert) makes it clearly distinct from list_projects, describe_input_kinds and list_terrain_sources without needing the schemas.

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?

Explicitly says 'Use the row ids with create_scenario; this is the listing primitive — no need to probe files', giving both a downstream consumer and a negative instruction that steers the agent away from an alternative approach. It stops short of naming a sibling tool (e.g. describe_input_kinds) as the alternative, so it is not a full 5.

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