MODIS vegetation index at a point

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

Annotations already disclose readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond annotations: NDVI range (-1..1), EVI's sensitivity in high-biomass areas, 16-day composite period, and 250m resolution. 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 compact and efficiently organized: one core statement, then definitions of NDVI/EVI, then resolution and use cases. Every sentence adds value with no redundancy or fluff.

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?

The description covers the product details, index interpretations, resolution, and practical applications. Since an output schema exists, not describing the return format is acceptable. It could mention date range behavior or data caveats, but overall it is complete for a read-only point query tool.

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 clear descriptions for all four parameters, including WGS84 for coordinates and ISO dates with defaults. The description itself does not add parameter-specific details, but the schema handles this fully. Baseline 3 is appropriate.

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 it returns NDVI and EVI vegetation index from NASA MODIS MOD13Q1 at any coordinate. It distinguishes itself from all sibling tools, which cover different domains like weather, earthquakes, and poverty. The data source and indices are specific, avoiding tautology.

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 gives explicit use cases: 'agricultural monitoring, deforestation tracking, drought stress indicators.' This provides clear context for when to use the tool. However, it does not mention alternatives or exclusions, and there are no direct sibling tools for vegetation index, so the lack of explicit 'when not to use' is not a major gap.

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