Crypto narrative indices (AI, RWA, DePIN, meme, L1, L2, DeFi, quantum)

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

Beyond the readOnlyHint and openWorldHint annotations, the description discloses index construction (equal-weight, fixed basket), the rebase date (2025-01-01), the available return windows (1d/7d/30d/90d/YTD), the BTC comparison, and the member lists. It also transparently warns that daily points are omitted unless include_points is true and that include_points returns a large payload.

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?

Two sentences, no filler. The first sentence front-loads the trigger conditions, and the second packs the output details into one clear, scannable statement. Every element 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 carries the burden of explaining return values, and it does so thoroughly: what indices, how constructed, base date, return windows, BTC comparison, member lists, and the include_points caveat. For a simple one-parameter tool, this is complete.

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?

The schema covers the single boolean parameter include_points with a description, and the tool description adds the default behavior: daily points are omitted unless include_points is true. This extra information about the parameter's effect on response size is valuable beyond the raw schema.

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 resource ('eight equal-weight fixed-basket indices') and the exact narrative categories (AI, RWA, DePIN, memecoins, L1, L2, DeFi, quantum), making it unmistakably distinct from generic market-index or single-asset tools. The trigger phrasing 'which crypto narrative or sector is leading' and 'for a theme index' gives the agent a direct signal for when this tool applies.

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?

It provides clear when-to-use context: narrative leadership, sector rotation, or theme index requests. It does not explicitly name alternatives or state when not to use this tool, so it stops short of a 5, but the trigger conditions are specific enough to route the agent correctly.

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