modify_order

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

Annotations already indicate mutation (readOnlyHint=false) and destructive potential (destructiveHint=true). The description adds value by requiring TOSS_ENABLE_TRADING=true and detailing critical constraints (quantity required for KR, omitted for US; price required for LIMIT, omitted for MARKET). It does not disclose side effects like whether partial modifications are supported or if confirm_high_value_order triggers extra confirmation, but the bar is lowered by 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 and front-loaded: the first sentence states the core purpose, the second gives a key prerequisite, and the final lines concisely encode market-specific rules. Every sentence adds necessary context without fluff, achieving high information density in under 50 words.

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 having 6 parameters and no schema descriptions, the description covers the most critical usage constraints (market differences, order type rules, trading flag). It is slightly incomplete around account_seq and confirm_high_value_order, and the presence of an output schema reduces the need to explain return values. Overall, it provides enough context to use the tool correctly in most cases.

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 0%, so the description must compensate. It adds meaning for order_type (LIMIT vs MARKET), price (required for LIMIT, omitted for MARKET), and quantity (KR required, US not supported), and order_id is implied as the open order's ID. However, account_seq and confirm_high_value_order are not explained at all, leaving 2 of 6 parameters semantically opaque.

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 'Modify an open order's price/quantity' with a specific verb and resource, and the scope (price/quantity) distinguishes it from create_order and cancel_order. The focus on open orders and explicit field modifications makes 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?

The description provides clear context for when to use the tool: modifying open orders, with explicit prerequisites (TOSS_ENABLE_TRADING=true) and market-specific rules (KR vs US stocks, LIMIT vs MARKET). However, it does not explicitly contrast with alternatives like cancel_order or mention scenarios where modification is inappropriate (e.g., already filled orders), so it stops short of a 5.

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