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

Annotations already declare readOnly, idempotent and non-destructive behavior, so the safety profile is covered. The description adds value beyond that: it asserts the schema is authoritative and that shapes, custom properties and paths keep their existing editor meanings, which shapes how the agent should interpret the result. It does not describe the return shape or size.

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, front-loaded with the action ('Read the authoritative JSON Schema before composing a map'). Every clause carries distinct, actionable information with 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?

No parameters and no output schema, but the tool's own output is the JSON Schema, which the description names. Combined with the interpretation notes, an agent has enough to call it correctly at the right moment in the map workflow. A brief note on the schema's scope or size would make it fully complete.

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 tool takes zero parameters, so there is nothing to mis-specify; the baseline for a no-param tool applies. The description correctly implies a static, argument-free read of the schema.

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: read the authoritative JSON Schema for map documents. An agent can identify it as the schema-source tool. However, it never distinguishes itself from similar-sounding siblings such as map_authoring_context or map_workbench_context, leaving some ambiguity about which read to choose.

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?

It gives a clear precondition — read this 'before composing a map' — which tells the agent when in the workflow to call it. It also implies correct behavior via 'use assetRef instead of inventing image URLs'. It stops short of naming alternatives or stating when not to use it.

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