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

Annotations declare readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=false, so the safety profile is partly covered. The description adds valuable context: it is a paper preview, in-sample with no holdout, consumes quota, and warns against submitting private strategies. However, what mutation occurs is not fully spelled out.

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 short and front-loaded with 'PAPER PREVIEW', but the cryptic flags (sealed:false, is_keep:false, paper:true) and bilingual phrasing add noise rather than clarity. Every sentence does not fully earn its place due to undefined jargon.

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?

Given a single-parameter backtest tool with an output schema, the description covers the key call-time context: it is a paper preview, in-sample without holdout, consumes quota, and has privacy restrictions. The only minor gap is the unexplained flag terms, but overall an agent has enough to invoke it correctly.

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%, with the single parameter 'arenascript' already documented as a script up to 20,000 characters. The description does not add syntax or format details beyond the schema, so the baseline of 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 it is a paper preview backtest of an ArenaScript, an alias of backtest_strategy, running the Lab's Rust engine on server OHLCV candles at the declared timeframe, in-sample without holdout. The core verb+resource are clear, though the cryptic flags (sealed:false, is_keep:false, paper:true) and bilingual text slightly obscure the message.

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 'Not a verdict; for a verdict use get_lab_desktop_handoff', naming the alternative and the condition that selects it. Also advises that public scripts may be kept and private strategies should not be submitted, giving clear boundaries.

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