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

Annotations establish the mutation profile (readOnlyHint=false, idempotentHint=false), so the description's job is to add context — which it does by disclosing the non-obvious traversal semantics of pathLookup (walks chains to any depth, follows dependsOn direction) and the empty-filter idiom. It does not mention side effects such as a link field creating the reciprocal field in the linked table, which is a meaningful omission for a create operation.

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?

Three sentences, front-loaded with the core action before the specialized detail. The pathLookup sentence is long and clause-heavy but every clause carries information an agent would otherwise have to guess.

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 create tool with no output schema and a 20-type nested field object, the description covers the hardest case (pathLookup) but omits the create/update/delete sibling boundaries and what happens on failure or with duplicate names. The rich schema carries most of the remaining burden, so this is adequate but not complete.

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 33%, and the nested object is already extremely well documented in the schema itself (every option field carries its own description). The description adds real meaning for targetTable/direction/maxDepth/targetFilter but says nothing about baseId or the top-level field container, and covers only 1 of the 20 enum field types.

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: 'Add a field to a table.' The word 'add' distinguishes it in spirit from update_field and delete_field, and the rest of the description narrows it to a specific field type (pathLookup). It never names a sibling explicitly, so an agent must infer the create-vs-update and create_field-vs-generate_ai_field boundaries.

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?

Usage is implied by the description of pathLookup semantics and the empty-filter trick, but there is no explicit 'use this when…' statement, no exclusion of update_field/generate_ai_field, and no mention of prerequisites such as needing an existing table or write permissions.

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