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

Goes well beyond the read-only/idempotent annotations by disclosing a critical semantic rule: a month with no JODI submission returns {reported:false, value:null} and NEVER 0, with the reason (self-reported data, skipped/delayed months). It also notes 'Keyless', informing the agent no auth is required. This is exactly the kind of behavior an agent cannot infer from structured fields.

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-loads the core statement, then behaviors, then worked examples — a logical order with little waste. It is slightly long due to the enumerated flow/product lists and two full example calls, but each element carries real informational value.

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?

For a keyless read tool with no output schema, it covers purpose, allowed values, defaults, the missing-data convention, and concrete invocation examples — enough for correct use. The return shape is only partially described (the null case), which is a minor residual gap.

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%, so the schema already documents country, flow, product, months, and end_month in detail. The description largely echoes those enumerations and adds only example values; it does not add syntax or constraints beyond what the schema supplies, so baseline 3 applies.

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?

Opens with a specific verb+resource+scope: 'Monthly JODI-Oil series for one country', then enumerates the exact flows and products available. An agent can immediately tell this apart from jodi_oil_compare, jodi_gas_series, or jodi_countries without opening any 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?

Provides three concrete question templates ('Saudi crude oil production over the last two years', 'UAE crude exports vs a year ago') that map directly to call patterns, giving clear context for when this tool fits. It does not explicitly state when to prefer this over jodi_oil_compare, so the routing guidance is implied rather than exhaustive.

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