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. It fully discloses the output format (regimes, confidence, price vs MA, VIX level, duration), the update frequency (every 30 minutes), and the cost (FREE, no API key). No side effects or destructive actions are relevant, and it explicitly notes the update cadence, which is a key behavioral trait.

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 longer than average but each sentence serves a purpose: purpose, usage, output details, update frequency, and cost. It is front-loaded with the core purpose and structured logically. While it could be tightened, the detail is valuable for a tool that returns complex regime 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?

For a no-parameter tool, the description is fully self-contained. It explains what it does, when to use it, what it returns (including specific regime definitions), how often it updates, and any access requirements. There is no output schema, so the description must cover return values, and it does so thoroughly.

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?

The tool has zero parameters, so the schema is empty. The description doesn't need to explain parameters, and the baseline of 4 is appropriate. It does not add any parameter-related semantics, but none are needed.

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 clearly states the tool's purpose: 'Detect the current market regime to inform trading strategy.' It specifies the resource (market regime) and the action (detect), and explicitly lists the four possible output regimes (BULL, BEAR, SIDEWAYS, CRISIS) with their definitions, distinguishing it from sibling tools that handle different market data.

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 usage direction: 'Use this tool alongside get_risk_index before making trading decisions.' It also mentions that it's free and requires no API key, which is relevant context. It doesn't explicitly state when not to use it, but the guidance is clear and practical.

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