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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is fully covered. The description adds 'server-authoritative' and 'replay' context, which gives some behavioral insight beyond the annotations, though not deep detail about response size or edge cases.

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 one tight sentence with zero filler. 'Read' is front-loaded, and the resource is specified precisely.

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?

For a read-only, idempotent, non-destructive tool with one parameter, a complete input schema, and an output schema, the description is sufficient. An agent can determine how to invoke and what to expect without additional information.

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% for the single required parameter matchId, and the pattern is fully documented. The description adds no extra meaning beyond identifying that the tool operates on one match; the schema already documents the parameter.

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 action ('Read') and a specific resource ('server-authoritative state and replay for one SWARM SYNC match'). The title and description together clearly distinguish it from sibling tools like get_arcade_player_status or play_arcade_move by focusing on match state and replay.

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 clearly implies the tool is for reading a single match's state and replay. It does not explicitly name alternatives or when not to use it, but the singular 'one match' plus 'read' gives strong contextual guidance.

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