Run Scanner

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

The annotation readOnlyHint=true already indicates a safe read operation. The description adds valuable behavioral context about the brokerage session: 'auto-acquired, auto-releases after idle,' which informs the agent that no explicit authentication call is needed and that the tool manages the session lifecycle. This goes beyond the annotations and is useful for planning execution.

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 two sentences, front-loaded with the main purpose and followed by the essential session requirement. Every word adds value; there is no repetition of schema or annotation content, and it is appropriately sized for a tool of this complexity.

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 strong schema coverage and the readOnlyHint annotation, the description adds sufficient context about purpose and operational prerequisites. It lacks details about the return format or potential errors, but in the absence of an output schema, the description covers the essential aspects for an agent to invoke the tool 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?

Schema description coverage is 100%, with each parameter described in the schema (e.g., type, location, instrument, filters). The description does not add additional semantic detail beyond the schema, so the baseline of 3 applies. It only loosely refers to 'specific criteria' without elaborating on parameter formats or dependencies.

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's function: 'Execute a market scanner to find securities matching specific criteria.' It uses a specific verb ('Execute') and a distinct resource ('market scanner'), which distinguishes it from the many data-retrieval siblings like get_scanner_params and get_market_snapshot.

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 implies when to use the tool ('to find securities matching specific criteria') but does not explicitly compare it to alternatives or state exclusions. It mentions the brokerage session prerequisite, but this is more about operational context than usage guidance. No mention of using get_scanner_params first or when not to use this tool.

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