get_latest_candles

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

Annotations already declare readOnlyHint=true, and the description adds useful context: it explains the 'complete' field semantics (false = still forming), that prices are decimal strings, and the structure per requested price side. This goes beyond the schema and annotations, though it does not cover rate limits or other operational traits.

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 description is concise and front-loaded: a single, clear purpose sentence followed by an efficient return-format example. Every sentence adds value without redundancy.

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?

Given the tool's moderate complexity, the description is complete. It details both the request shape (implicitly via schema) and response shape, including field semantics. The presence of an output schema reduces the need to explain return structure, and the description fills the remaining semantic gaps.

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?

The input schema contains a detailed description of the candle_specifications parameter, including the exact format and allowed values, so schema coverage is 100%. The tool description does not add extra parameter semantics, so baseline 3 is appropriate.

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 opens with 'Get the most recent candle for each requested instrument/granularity', which is a specific verb+resource+scope. It clearly distinguishes from siblings like get_candles by focusing on 'latest' and the per-specification response structure.

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 implies usage (when you need the latest candle) but does not explicitly state when to use this tool versus alternatives like get_candles. No exclusions or comparisons are provided, so it stops at implied usage rather than clear guidance.

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