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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, not open-world), so the bar is lower, yet the description still adds genuine context: no API key needed, no orders placed and no funds moved, numbers that fail a plausibility check are withheld rather than guessed, and every number carries a source and timestamp. The no_simulation status case is a useful disclosed failure mode. It stops short of describing pagination or latency behavior.

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 scope, percentile definitions, and the critical 'quote the range, never a single target' instruction are all front-loaded in the first two sentences. The remaining clauses are short and each carries an operational fact rather than filler, though 'From EventTrader's crypto dashboards (cymetica.com/crypto)' and 'Not financial advice' are more provenance branding than actionable content.

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?

There is no output schema, so the description must explain the return shape, and it does: percentile bands for six horizons plus the below-current-price path share, with a named degraded status. Combined with annotations covering safety, an agent has enough to call and interpret it, with the unresolved sibling overlap as the main gap.

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 with their accepted values (1mo through 5y, omitted meaning all). The description's mention of the six horizons and the 5th/middle/95th percentile definitions adds framing but no new per-parameter syntax beyond what the schema provides. 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?

The first sentence states a specific verb-and-resource: it returns the simulated price range for one coin across six horizons, plus the share of paths ending below today's price. That is far more specific than the name alone. However, it does not distinguish itself from the sibling get_crypto_outlook, which by name looks like the same capability, so an agent has no basis for choosing between them.

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 gives real usage constraints: quote the range rather than a single target, treat results as scenario simulations rather than forecasts, and expect status=no_simulation when the price history cannot be proven to belong to this coin. But it never says when to reach for this tool instead of the near-identical sibling get_crypto_outlook or the other crypto_* tools, so routing guidance is implied at best.

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