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

Annotations already declare readOnly/openWorld/non-destructive, so the safety profile is covered. The description adds real behavioral substance beyond that: analysis is restricted to fully closed candles, so no look-ahead leakage in the base path, and date-only requests return a 1-hour OHLC summary plus multi-timeframe context as of end-of-day. It does not reconcile that no-look-ahead promise with include_forward_window.

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, front-loaded with the core constraint ('completed candles only') before the input forms. The final sentence partly repeats the date parameter's schema description, which is the only redundancy, but overall nothing is padded.

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 carries return-value burden, and it only explains the date-only response. It never says what a timestamp-addressed or time-addressed request returns, nor what include_forward_window does to the result, leaving an agent to guess on half the call shapes.

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 contributes beyond the schema by making the date/time and ISO 8601 timestamp forms explicitly alternative addressings and by stating what a date-only request yields. The one parameter it omits entirely is include_forward_window, whose schema text ('Minutes to look forward') is the thinnest in the set.

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 — reconstruct historical market context — and scopes it to completed candles only, which separates it from live-context siblings like get_market_context and get_market_snapshot. It never names those siblings explicitly, so the differentiation is implied rather than asserted.

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 explains how to address a point in time (date + optional time, or an ISO 8601 timestamp) but says nothing about when to prefer this over get_market_context, get_market_snapshot, or get_market_events. Usage is implied by the word 'historical' rather than stated as a selection rule.

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