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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so the safety profile is covered. The description still adds genuine behavioral context beyond them: the default-true map behavior, a concrete screenshot payload size (~100-500KB) and a usage cadence warning about context cost. It stops short of describing return shape or ordering, but the payload size and default disclosure are real added value.

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 with the payload contents, then the two optional flags, with nothing idle. It is dense — the em-dash clauses packed into the map and screenshot sentences make it read heavier than needed — but every clause carries operative information.

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?

With no output schema and only three optional params, the description carries the burden and discharges it: it lists what is returned, gives defaults, sizes the screenshot cost, and explains the omitted-sceneId fallback. Nothing an agent needs to 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?

Schema description coverage is 100%, so the baseline is 3 and the schema already documents all three parameters including their defaults. The description largely restates those same semantics (default true, size range, omit for active scene) rather than adding new parameter-level meaning, so it sits at, not above, the baseline.

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 ('Get') and resource ('scene') and enumerates the payload contents: tokens with HP/AC/conditions/grid positions, walls, lights, notes, regions. It also differentiates itself from the sibling scene-list by noting that scene-list supplies the IDs, so an agent can route between them without opening a schema.

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?

Gives explicit conditional guidance: includeMap=false 'when you only need the lists', includeScreenshot=true for a first view but not every turn, and sceneId omitted means the active scene. It names the alternative tool (scene-list) for ID lookup, so the when-to-use decision is fully specified.

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