Historical context for any recorded metric (conditional distribution)

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

Annotations already mark it read-only and open-world, and the description adds substantive behavioral detail: buckets under 30 days are suppressed, most metrics do not separate from the base rate, and the interpretation says so plainly. That is exactly the kind of caveat an agent needs before reporting a result to a user.

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?

Front-loaded with the trigger, then the mechanics, then the honesty rules — a sensible order with no filler sentences. The trailing metric enumeration is long but functional, listing the namespace rather than restating the schema.

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 single-parameter read tool with no output schema, the description carries the full burden and does so: it describes the returned fields (median forward BTC return, up-share at +1/+3/+7 days, all-days base rate), the suppression threshold, and the interpretation caveat. Nothing needed to call or interpret it is missing.

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% with a pattern constraint and four example keys, so the baseline is 3. The description adds real value by enumerating the full accepted metric namespace (dvol_btc, vpin_btc, fred_* series, btc_* network series), which the schema only hints at.

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 and resource — bucketing a metric's current value against its own daily history and returning forward-return statistics per bucket. Distinguishes itself from sibling lookups like get_series or get_market_profile by framing the output as conditional distribution vs. base rate.

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?

Opens with an explicit trigger condition: call it when the user asks if a reading is high/low or what happened after similar readings. It also sets an explicit boundary with 'History, not a forecast,' telling the agent 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.