set_test_mode

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

With no annotations provided, the description carries the full burden of behavioral disclosure, and it delivers: it states the concrete consequences of both states ('spend only gray test coins in test stores' vs 'hide test stores and spend real coins'), a permission boundary, and an operational directive ('After a real wallet top-up, suggest turning test mode off'). This is rich behavioral context, not merely a restatement of the tool's name.

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?

Every sentence earns its place: purpose, then triggers, then policy boundary, then redirection, then a suggestion rule, then state consequences. The description is front-loaded with the core operation and immediately tells the agent when to fire it. No filler or redundancy; the length is justified by the density of distinct operational facts.

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 one-boolean-parameter tool with no output schema and no annotations, this description is operationally complete: an agent knows when to call, what each state does, what the agent may and may not change, and how to route a closely related intent elsewhere. The only gap is the exact response format, which is minor for a toggle operation and not covered by an output schema.

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%, and the schema already documents enabled fully ('true = test stores + gray coins. false = live stores + real coins, hide test shops'). The description's behavioral clauses largely echo that same meaning ('spend only gray test coins in test stores' / 'hide test stores and spend real coins'), adding no genuinely new information beyond what the schema provides. Baseline 3 is appropriate.

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 opening sentence, 'Turn AgentPay test mode on or off,' is a specific verb+resource statement that leaves no ambiguity about the operation. It also distinguishes itself from siblings by clarifying this is 'the only *policy* setting the agent may change' (contrasting with get_spending_policy) and explicitly redirecting home-address saves to save_delivery_address.

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 gives explicit invocation triggers, including quoted natural-language phrases from the owner ('включи тестовый режим', 'хочу в настоящие магазины') and a post-condition ('after a real top-up when they agree to leave the sandbox'). It also names the alternative tool for a related but distinct intent (save_delivery_address), leaving no ambiguity about when to choose this tool over a sibling.

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