Search tradeable instruments

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

With annotations already indicating read-only, idempotent, and open-world behavior, the description adds valuable context beyond those flags: results are ranked with exact symbol/ISIN matches first, and it searches the entire Trading 212 catalogue rather than account holdings. This clarifies expected behavior and prevents misuse without contradicting the 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 three sentences long, front-loaded with the main action, followed by usage guidance and a clarifying scope note. Every sentence earns its place—no fluff, no repetition of schema details, and the alternative tool is mentioned naturally within the scope distinction.

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 no output schema, the description explains the key output concept (exact tickers like AAPL_US_EQ), the ranking behavior, and the critical scope distinction from holdings. Combined with rich annotations (readOnly, idempotent, openWorld) and full parameter documentation, the agent has everything it needs to invoke the tool correctly without missing context.

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?

The schema covers 100% of parameters with detailed descriptions (e.g., query supports company name, symbol, or ISIN with case-insensitive partial matching). The description adds no new parameter-level semantics beyond the schema, so a baseline score of 3 is appropriate given the thorough schema coverage.

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 'Finds instruments in the Trading 212 catalogue by company name, symbol or ISIN', giving a specific verb, resource, and search criteria. It also distinguishes itself from t212_list_positions by explicitly saying it searches the catalogue, not account holdings, which sets it apart from siblings.

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?

Provides explicit when-to-use guidance: 'Use this first whenever you have a company name but not a ticker.' It also names a direct alternative for account holdings: 'use t212_list_positions for what is actually owned.' This is clear and actionable, leaving no ambiguity about when to choose this tool.

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