Bitcoin cycle indicators: Pi Cycle, Mayer, 200W MA, Puell, S2F

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so no destructive behavior needs disclosure. The description adds useful behavioral context beyond annotations: data is recomputed nightly from a first-party close record since 2012, the daily series is optional and large, and the output is explicitly 'Levels, not forecasts.'

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 sentences with no filler. The trigger is front-loaded, followed by return contents and a useful caveat. Every sentence contributes to effective tool selection or invocation.

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 no output schema, the description adequately describes what will be returned: latest readings, Pi Cycle cross dates, and optionally the daily series. It also states the data source and recomputation cadence. It could be slightly richer about the exact response shape, but the information needed to call the tool correctly is present.

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%, so both parameters are already documented. The description adds value by flagging the daily series as 'large,' warning agents about response size when include_points is true, and by indicating that the default behavior is latest values and cross dates only.

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 opens with a specific trigger ('Call this when the user asks whether Bitcoin is near a cycle top or bottom') and enumerates the exact indicators covered, which clearly identifies the tool's resource and scope. It does not explicitly name a sibling alternative, but the indicator list is distinctive enough to separate it from the many market-data siblings.

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 context by telling the agent exactly which user intents and indicator names should trigger this call. It lacks an explicit 'when not to use' or named alternatives, but the closing caveat 'Levels, not forecasts' helps set expectations about what this tool is not for.

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