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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds value by explaining the conceptual meaning of each signal option, which aids the agent in interpreting the result. It does not describe the return format, but given the read-only nature and simple parameter, this is acceptable.

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 three concise sentences that front-load the purpose, then list the parameter meanings, and end with usage guidance. No wasted words or redundancy.

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 tool with a single parameter and no output schema, the description covers the purpose, parameter semantics, and usage context. It stops short of stating the return format (e.g., numeric value, JSON), but given the simplicity, this is a minor omission.

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 schema provides only an enum list with zero description coverage. The description fully compensates by explaining each enum value: 'macro' is the market-regime read, 'energy' the macro energy balance, and 'crypto' crypto positioning and funding. This is exactly the semantic enrichment 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 role as a 'whole-market gauge' and differentiates it from per-company tools. It enumerates the three specific signal types ('macro', 'energy', 'crypto') with their meanings, making the purpose unmistakable.

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 explicitly tells when to use the tool: 'Use these for the backdrop a single name is trading against.' It also contrasts with per-company tools, implying that for individual equity signals, one would use a different tool. This provides clear context though it does not name specific sibling alternatives.

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