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

With no annotations, the description carries the full burden and does so: it enumerates the return fields and status values (ok, cloudy, no_scene), states that missing scenes return 404 and are not charged, and discloses the $0.012 USDC x402 payment requirement on Base/Solana. That covers cost, error behavior, and response shape an agent needs before invoking.

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?

Front-loaded with the use case, then inputs, outputs, edge case, and price in a compact telegraphic style with no filler. Minor friction from the run-on 'Example: ?lat=... Price: ...' and an example without a base URL, but nothing is wasted.

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?

No output schema exists, yet the description fully specifies the returned series fields, aggregate min/max and change, the no-scene outcome, and payment mechanics. For a 5-parameter read tool with no annotations, an agent has everything needed to call it 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 coverage is 100%, so the baseline is 3; the description goes beyond it by adding the radius_m valid range (200-10000), the months range (1-12), and a concrete example query. It still lets the schema do most of the per-parameter work.

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?

States a specific activity (tracking crops, greenery, land change month by month) and the concrete resource (per-month JSON with NDVI mean/median, cloud %, scene status). The phrase 'Numbers only, no images' implicitly separates it from satellite_image and satellite_compare, so an agent can pick it without opening the schema.

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?

'Use when tracking crops, greenery or land change month by month' gives a clear triggering context, and the inputs/limits (radius 200-10000, months 1-12) scope it further. There is no explicit when-not or named alternative, which keeps it just below a 5.

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