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

Annotations already establish readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description goes further by disclosing the simulation rules ('buy a slice on every step_pct drop below the lowest open buy, sell each slice at +target_pct, never at a loss') and the shape of the result, which is real behavioral context beyond 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?

Two dense sentences with the core mechanics front-loaded and no filler. The only blemish is 'since 2019', which conflicts slightly with the schema default of one year before the last candle, and the trailing list of outputs is slightly compressed.

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 correctly compensates by naming the returned metrics (realized %, trades, open positions, buy-and-hold). Combined with 100% schema coverage, an agent has enough to call it correctly, though the effective date window remains ambiguous given the 'since 2019' phrasing.

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%, so the baseline is 3, but the description adds genuine meaning by explaining the mechanics of step_pct (drop threshold below the lowest open buy) and target_pct (sell threshold). slices, fee_pct and the date bounds are left to the schema, which is acceptable given full coverage.

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 gives a specific verb and resource: simulate a buy ladder on Bitvavo BTC-EUR daily candles. It names the exact strategy mechanics (slice on step_pct drop, sell at +target_pct) and is plainly distinct from siblings like lookback_calculator, bitcoin_drawdown and get_weekly_results.

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?

Usage is implied by the description of what the simulation does, but there is no explicit 'use this when' or 'use X instead' statement, nor any stated prerequisites. An agent can infer the purpose but gets no routing guidance against the other analytical tools in the sibling set.

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