Index history

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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description adds genuinely new behavioral context: the return shape (close, high, low, percent change) and the ordering (newest first), which an agent needs to interpret results.

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 tight sentences: the return payload and ordering come first, the lookup helper second. No filler, and the most decision-relevant information is front-loaded.

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 two-parameter read-only history tool with full schema coverage and no output schema, the description covers purpose, output fields, ordering, and the name-resolution path. Nothing essential is missing, though a note on grain (daily bars) versus sibling tools could sharpen it further.

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 100%, so both parameters are already documented with ranges and defaults. The description adds only that indices may be total, equal-weight, or sector-based, which slightly clarifies the domain of the 'index' argument but adds nothing about 'days'.

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 set (returns daily close, high, low and percent change) for a specific resource (a TSE index), and explicitly scopes the index universe (total, equal-weight, sector). This clearly separates it from ts_price_history (per-symbol prices) and ts_indices (name lookup).

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?

Explicitly routes the agent to ts_indices when the index name is unknown, which is the main prerequisite for calling this tool. It does not state when-not to use it (e.g. versus ts_price_history for equities), so it stops short of full alternative coverage.

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