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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds context about staleness and sensor down states, but does not explicitly reiterate side-effect-free operation; still, no contradiction exists.

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 mostly concise but repeats the idea of bundling three reads in both the intro and the return statement. This slight redundancy does not impede understanding, but a tighter version would be cleaner.

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?

The description fully covers the tool's purpose, what it returns, the importance of health checks, and the free-tier availability. It provides sufficient context for an agent to decide when and how to invoke it, without needing to inspect the 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?

There are zero parameters, and the description makes clear that no inputs are required. The coverage is complete, and the description effectively communicates that the tool is a bundled read with no configuration 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 as the canonical current market state, bundles three specific reads, and emphasizes it as the first call to make. It distinguishes itself from siblings by focusing on market state rather than audit, funnel, or system status.

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 instructs to 'Call this FIRST' and advises checking health before trusting a directional read, which is actionable guidance. The mention of bundling three public reads further clarifies typical use cases.

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