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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds real value on top: a hard 100-symbol cap, rate-limit pressure, and the guarantee that unknown symbols surface in unresolvedSymbols rather than being dropped. It stops short of describing what 'current data' actually contains per asset, which matters since there is no output schema.

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, no filler, and the scope ('up to 100 symbols in a single call') is front-loaded before the routing advice and the return-value caveat. Every sentence carries a distinct piece of information.

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?

For a one-parameter batch read with annotations and no output schema, this is nearly complete: limits, alternative, and the unresolvedSymbols escape hatch are all covered. The remaining gap is the payload shape of the 'resolved assets' — an agent cannot tell whether it gets quotes, profiles, or full series, which the lack of an output schema makes the description's responsibility.

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 already documents the array, the 100-item cap and the ticker format, so the baseline is 3. The description adds the non-obvious constraint that the list must be 'explicit' (no patterns or ranges) and that unknown entries are reported back rather than erroring, which changes how an agent should build the input.

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 ('Get current data for an explicit list of ... symbols') plus the batch scope ('in a single call', 'up to 100'). It explicitly names the sibling it replaces (get_asset_quote) and the contrast with a per-symbol loop, so an agent can distinguish it without opening any schema.

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?

Explicit routing guidance: 'Use this instead of calling get_asset_quote repeatedly', with the reason (rate-limit exhaustion). The word 'current' also signals the boundary against the historical sibling get_assets_as_of, though that exclusion is left implicit.

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