search_instruments

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true. The description adds value by confirming it returns a formatted Markdown table or error message, and by specifying that it performs a lookup without side effects. No contradictions with 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 well-structured with Args and Returns sections, making it easy to parse. While slightly verbose with the docstring format, every sentence adds useful information without redundancy.

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 low complexity, full schema coverage, and presence of annotations and output schema, the description provides all necessary context: purpose, parameter behavior, examples, return format, and error handling. No gaps identified.

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 coverage is 100% with clear descriptions for both parameters. The description adds value by providing concrete examples (e.g., 'Apple', 'META', '0000320193') and stating the default search method, which goes beyond the schema alone.

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 the tool searches for ticker symbols by multiple identifiers (company name, symbol, CIK, CUSIP, ISIN), which is a specific verb+resource combination that distinguishes it from sibling search tools like search_by_category or search_metrics.

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 explicitly lists the identifiers it supports and provides example queries, giving clear context for when to use it. It does not explicitly state when not to use it or mention alternatives, but the sibling tool names and the focused scope make the intended usage clear.

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