Fetch normalized market mover instruments from Google Finance using count, offset, and category filters to identify top gainers and losers.
Google Finance market movers. Returns normalized market mover instruments.
| Name | Required | Description | Default |
|---|---|---|---|
| count | No | Result count | |
| offset | No | Result offset | |
| categories | No | Comma-separated numeric categories |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, description carries full burden but only states it 'returns' data, implying a read operation. No details on authentication, side effects, or limitations.
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?
Extremely concise but sacrifices completeness. Front-loads purpose but omits necessary details.
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?
Lacks explanation of 'market movers', filtering logic, or output structure. Incomplete for a tool among many finance siblings with no output schema.
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 descriptions cover 100% of parameters, so baseline is 3. Description adds no extra meaning beyond what the schema already provides.
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 is specific with verb 'returns' and resource 'normalized market mover instruments', clearly distinguishing it from siblings like google_finance_markets_top or google_finance_markets_featured.
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?
No guidance on when to use this tool versus other Google Finance market tools. No explicit context or alternative recommendations.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.