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

Annotations declare readOnlyHint=true, and the description adds valuable context: it discloses the update frequency ('Updates: weekly'), the score scale and interpretation, and indirectly mentions the Gold tier requirement via the schema. It does not describe return format or rate limits, but for a read-only tool this is adequate.

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 two sentences with no waste. It front-loads the core mechanism (score range, interpretation), then lists outputs and usage triggers. Every sentence earns its place.

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 the simple read-only nature, the tool is well covered. The description lists output fields and usage context, while the schema covers the optional parameter and tier requirement. It lacks an output schema, but the description names the fields explicitly, making it complete enough for an agent.

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% for the single optional 'days' parameter, and the schema itself provides detailed semantics (returns history series up to 5 years, requires Gold tier). The description adds no parameter-specific meaning beyond the schema, so the 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 description clearly states the tool returns a 0-100 Bitcoin whale-flow pressure score, with detailed interpretation (above 65 accumulation, below 40 distribution) and a list of output fields. This specific verb+resource+scope fully distinguishes it from sibling tools.

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?

Explicit usage guidance is provided: 'Call when the user asks about BTC whales, large holders, smart money, on-chain flows, or whether whales are buying or selling, or when timing BTC allocation shifts, crypto rebalancing, or funding-rate position adjustments.' This gives clear triggers and context for selecting this tool.

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