get_equities_bars_daily_am

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

Annotations already indicate readOnly, non-destructive, idempotent, and open world. The description adds valuable context: data freshness (updated 12:00 JST, expires next day 6:00 JST) and premium access restriction, enhancing transparency without contradicting annotations.

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 (6 sentences) with key information front-loaded. Every sentence adds value: purpose, usage keywords, timing, sibling reference, parameter details. No redundant or filler content.

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?

Despite the tool having one optional parameter and no output schema details needed, the description covers all necessary context: what the tool returns, when to use it, data lifecycle, access restrictions, parameter semantics, and relation to sibling tools. It is fully sufficient for an AI agent to invoke correctly.

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?

With 0% schema description coverage, the description fully explains the 'code' parameter: format (5 digits, with special note on 4-digit codes), example, and behavior when omitted (retrieve all stocks). This is essential for correct parameter usage.

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 it returns Today's morning session OHLC bars (前場株価) and is premium only. It distinguishes from sibling get_equities_bars_daily by explicitly mentioning it's for historical data, making the purpose unambiguous.

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 provides explicit usage scenarios (前場, 前場終値, etc.), notes premium requirement, and gives a clear alternative for historical data (get_equities_bars_daily). The timing of updates and expiration further guides appropriate use.

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