Describe Filter Dimension

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely valuable behavioral context beyond that: it discloses that some dimensions are 'silently stripped due to upstream bugs' and that alternative tool suggestions are provided. It omits return format, but that is carried by the output schema.

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 sentences, zero waste, and the payload of what is returned is front-loaded before the timing advice. Every clause earns its place.

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 values need no explanation, and the description still summarizes the returned content (native support, stripped dimensions with alternatives, example values). Nothing an agent needs in order to call 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?

With a single parameter at 100% schema description coverage, the schema already documents the dimension name, case-sensitivity, and examples. The description's examples ('event_name', 'pathname', 'country') largely restate the schema, adding marginal value, 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 ('look up which tools accept a given filter dimension') and enumerates the three things it returns: native support, silent stripping plus alternatives, and example values. No sibling tool performs this lookup, so it is unambiguous in context.

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 this before constructing a complex filters[] array,' giving a clear trigger condition. It does not name exclusions or a fallback for simple, non-array filters, but the positive guidance is unambiguous.

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