query_features

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the return format (GeoJSON FeatureCollection) and that parameters are optional, but lacks details on permissions, rate limits, error handling, or whether this is a read-only operation. For a query tool with zero annotation coverage, this is insufficient.

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 well-structured and concise, with a clear purpose statement followed by bullet-pointed Args and Returns sections. Every sentence adds value, and there's no redundant information. It's appropriately sized for the tool's complexity.

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?

Given 5 parameters, no annotations, and no output schema, the description is moderately complete. It covers the purpose, parameters, and return format, but lacks behavioral context (e.g., read/write nature, error cases) and usage guidelines. For a query tool with moderate complexity, this is adequate but has clear gaps.

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?

The description lists all 5 parameters with brief explanations (e.g., 'Optional CQL filter expression'), adding meaning beyond the schema, which has 0% description coverage. It clarifies optionality and purposes, though it doesn't provide examples or detailed constraints. Since schema coverage is low, the description compensates well, but not fully.

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 clearly states the tool's purpose: 'Query features from a vector layer using CQL filter.' It specifies the action (query), resource (features from a vector layer), and method (CQL filter). However, it doesn't explicitly differentiate from sibling tools like 'list_layers' or 'get_layer_info', which reduces it from a perfect score.

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 no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'list_layers' (for listing layers) or 'get_layer_info' (for layer metadata), nor does it specify use cases or prerequisites. This leaves the agent without contextual usage direction.

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