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

Annotations already declare readOnly/idempotent/non-destructive/openWorld=false, but the description adds genuinely useful operational context: refresh cadence (twice daily, ~07:30 and 13:30 Sydney), what the date field means (last completed day), and an explicit scope caveat ('descriptive data, not a price forecast or trading signal'). That is real disclosure beyond the structured fields.

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?

Purpose is front-loaded in the first clause, and the long second sentence is dense with return-field and tier detail rather than padding. It is on the long side, but nearly every clause (cadence, date semantics, disclaimer) 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?

With no output schema, the description compensates by enumerating the return payload (zone, 7- and 30-day change, six tier scores, 30 days of history) and the zone vocabulary. Combined with the asset enum and cadence note, an agent has everything needed to call and interpret this correctly.

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 coverage is 100% and the enum already documents BTC (default) or ETH, so the schema carries the parameter burden. The description adds meaningful model context (BTC uses 48 signals, Ethereum fewer) but no invocation-level detail beyond what the schema states; baseline 3 applies.

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?

States a specific verb+resource (current SMM score for BTC/ETH) and defines exactly what the score is: a 0-100 confluence score from weighted percentile-ranked signals in six named tiers. It explicitly distinguishes itself from the sibling get_market_snapshot, so an agent can route without opening either schema.

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?

Gives concrete trigger conditions ('where Bitcoin or Ethereum sits in its market cycle', 'how the cycle score has moved recently', 'which tier is driving it') and names the alternative plus the condition that selects it ('use get_market_snapshot instead for a one-line overview'). Nothing is left to inference.

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