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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds value by disclosing what the response contains (candles plus last price, change over window, high, low), a behavioral trait not in the annotations, but says nothing about rate limits, pagination, or window semantics.

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, with the primary purpose front-loaded and the input-format caveat second. Every clause 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?

No output schema exists and the description compensates by summarizing the return shape. The main symbol-format ambiguity is resolved. Minor gaps remain around interval/limit semantics and window length, but nothing critical for a correct invocation is missing.

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 0%, so the description carries the full burden. It resolves the key ambiguity for `symbol` (plain ticker vs market id), which is genuinely useful; `interval` is a self-descriptive enum and `limit` is bounded 20-500 with a default in the schema, so the remaining gap is modest rather than severe.

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 combination (OHLCV candles) plus the summary payload returned, which is concrete and distinguishable from siblings like get_orderbook_depth or get_funding_rates. It does not explicitly differentiate from adjacent tools such as scan_patterns or get_market_radar, so it falls short of a 5.

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 clarifies accepted input forms (plain ticker BTC/ETH/AAPL or an id from search_markets), which is real usage guidance and routes the agent to a sibling for id resolution. However, it gives no when-to-use guidance versus alternatives like get_market_radar or scan_patterns, 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.