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

Annotations already declare readOnlyHint and idempotentHint, and the description reinforces this with 'Read', 'display-only', and 'feeds no institution score'. It adds context about the board's scope and limitations, including the time-series route clarification, without contradicting the annotations.

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?

Three sentences, each earning its place: the first states the core purpose and contents, the second clarifies where time-series data lives, and the third covers invocation and scope limitations. It is front-loaded and free of filler.

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 zero-parameter read-only tool, the description is complete: it lists the returned board contents, clarifies the display-only cross-read, states the non-institution-score scope, and points to the public REST detail route for time-series. No output schema exists, but the description supplies the necessary return-value context.

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?

There are zero parameters, so the schema provides full coverage. The description explicitly states 'Takes no arguments', removing any ambiguity about invocation. This is the appropriate baseline for a no-parameter tool.

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 names the specific verb 'Read' and the resource 'BTC/ETH Crypto Regime board', then enumerates its contents: change-point state, log-SR statistic, last shift, observation count, and the cross-read against disclosed bank exposure. It also distinguishes itself by noting it feeds no institution score and is display-only, setting it apart from sibling boards.

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 clear context: it takes no arguments, is display-only, feeds no institution score, and is not investment advice. It also directs time-series needs to the public REST detail route. It does not explicitly name a sibling alternative, but the when-not-to-use signals are strong enough for an agent to route correctly.

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