Price performance

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

Annotations already cover safety (readOnly, idempotent, non-destructive), so the description's added value is the disclosure that the underlying data differs by market — daily candles for Egypt, mixed daily/weekly closes elsewhere, and that the 52-week range is computed from closes rather than intraday highs/lows. That is a real behavioral caveat affecting interpretation. It does not mention rate limits, auth, or latency.

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?

Front-loaded with the resource and the full metric list before the per-market data-source caveats. Dense but every clause carries information; the em-dash-heavy second sentence is slightly run-on but not 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 must describe returns, and it does so thoroughly (all return windows, three volatility horizons, range, drawdown). Combined with annotations and a fully documented 2-param schema, an agent has enough to call it correctly; only edge cases (insufficient history, units) are unaddressed.

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% and the enum already lists the four markets, so baseline is 3. The description adds meaning beyond the schema by tying each market to a different data source and granularity, which materially changes how the same `market` value affects the output.

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+resource ('trailing performance of one instrument') and enumerates exactly what is returned (returns windows, volatility, 52-week high/low, max drawdown, Thndr 1Y return). This clearly separates it from siblings like get_price_snapshot, get_price_history and the account-level get_portfolio_performance.

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 explains data provenance per market ('Egypt: from daily candles', 'US, UAE and others: from Thndr's closing prices') and points to `history` and `method`, which implies when results are granular vs coarse. However, it never states when to pick this tool over get_price_snapshot or get_price_history, so usage is only implied.

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