preflight_call_credit_spread

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

Annotations already declare readOnlyHint=true and destructiveHint=false. Description adds that it estimates costs and does not place an order, reinforcing safety. No contradictions.

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?

Description is well-structured with a brief overview followed by parameter list. Every sentence adds value. Could potentially shorten the parameter descriptions slightly, but overall efficient.

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 output schema exists, description doesn't need to explain return values. All parameters are documented with semantics, usage guidance clear, and no behavioral gaps. Completely adequate for a 7-param tool with rich annotations.

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?

All 7 parameters are described with meaning beyond schema: sell_contract_osi is lower strike, buy_contract_osi higher strike, limit_price is net credit (positive), time_in_force defaults to DAY, expiration_time required for GTD, account_id optional. Schema coverage 0% but description fully compensates.

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?

Clearly states it estimates costs for a Bear Call Spread (call credit spread) before placing. Specifies sell lower-strike, buy higher-strike, net credit. Distinct from siblings like preflight_call_debit_spread and place_call_credit_spread.

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 says 'before placing it' and 'Does NOT place an order.' This distinguishes it from place_call_credit_spread. Also indicates when to use: to estimate costs, not to execute. No confusion with other preflight tools.

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