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

Annotations declare readOnlyHint, idempotentHint, and destructiveHint, but the description adds behavioral details: returns points oldest-first, downsampling flag, UTC times, and cost. These go beyond the annotations and provide useful context for invocation decisions.

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 relatively concise, with a clear opening sentence and a structured Args list. Every sentence adds value, though the Args section partly repeats the schema. It is front-loaded with purpose and key details, but could be slightly more streamlined.

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 presence of an output schema (not evaluated here) and the tool's complexity, the description covers all four parameters, explains defaults, and notes special behaviors (downsampling, filing-cadence, UTC). It does not discuss error handling or edge cases, but 'bounded' implies constraints are handled. Reasonably complete.

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?

Despite 0% schema description coverage, the description's Args section clearly explains each parameter: metric (enum values), entity (dict from resolve_entity), granularity (default 1d), and max_points (default 500). This adds significant meaning beyond the bare schema, compensating for the lack of inline descriptions.

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 clearly states 'Bounded timeseries for an entity' and lists the three specific metrics (price, macro_series, etf_flows). It uses a specific verb-resource combination and adds scoping details like 'oldest-first' and UTC times. However, it does not explicitly distinguish from sibling tools like get_snapshot, leaving room for confusion.

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 provides some usage guidance, such as the note on etf_flows filing-cadence and the cost of 1 unit per call. It also mentions the entity input comes from resolve_entity. However, it lacks explicit when-to-use or when-not-to-use instructions, and does not reference alternative tools.

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