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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description adds behavioral value by disclosing what each domain record contains (coverage, last-updated date, observation count) and the domain code syntax, which is the only place returns are described since there is no output schema. It omits pagination/limit behavior detail beyond the schema.

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 what the resource is, followed by why it matters, the return shape, and search hints. Dense but mostly earns its place; the "FAOSTAT is the UN FAO's own service" clause is mildly promotional but supports trust in the routing decision.

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 no output schema, the description adequately explains what comes back and how it connects to sibling tools, and annotations cover the safety profile. Only minor gaps remain (no explicit note on the limit default behavior, though the schema documents it).

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 the schema by supplying concrete search terms ("production", "trade", "emissions", "food security", "prices", "land") and illustrative domain codes ("QCL", "FBS", "TCL", "RFN", "GT"), which materially help an agent form a query.

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 resource (the 69 FAOSTAT statistical domains) and what each record carries, and explicitly distinguishes itself from faostat_dimensions and faostat_data by naming what it returns for them. An agent can tell it apart from siblings without opening schemas.

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?

Positions the tool as the "AUTHORITATIVE starting point" for agriculture/food/trade/land/emissions questions and says its output feeds faostat_dimensions and faostat_data, which gives a clear workflow role. It does not state explicit when-not conditions or exclusions, so it falls short of a 5.

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