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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds useful context beyond annotations: it is public, read-only, and takes an optional timeframe filter. No contradictions with annotations.

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?

A single dense sentence that front-loads the resource and contents, then adds access traits and parameter guidance. Every phrase earns its place with no filler or repetition.

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 simple read-only getter with one optional enum parameter and no output schema, the description is sufficiently complete: it names the return contents, access level, and filter option. It could be more explicit about the response shape, but the listed contents give an agent enough to understand what to expect.

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 coverage is 100%, so the baseline is 3. The description adds meaning beyond the schema by clarifying that 'timeframe' is an optional filter and by enumerating its possible values. The schema description itself is largely a restatement, so the tool description compensates with the 'filter' semantics.

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 ('get'), a clear resource ('Arena market state'), and enumerates the returned contents: BLUE and RED team NAVs, current epoch, scoreboard, and live performance. This makes it easy to distinguish from sibling arena tools like get_arena_epoch or get_arena_orderbook.

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 frames when this tool is relevant: when the full current arena state is needed. It does not explicitly name alternatives like get_arena_epoch or get_arena_history or state when not to use it, so it falls short of a 5, but the context is unambiguous enough for an agent to select it correctly.

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