describe_table

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

Annotations already establish readOnly/idempotent/openWorld, so the description's real contribution is behavioral: inactive fields are omitted, dictionary overrides from parents are applied and listed, and default_value/dependent/choices appear only conditionally. It also discloses that the response carries a cache_name pointing at sys_db_object, sys_dictionary, sys_dictionary_override and sys_choice, which is useful context beyond the annotations, though permissions and failure modes are not addressed.

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 purpose is front-loaded in the first clause, and every sentence carries substantive content about return shape or usage. It is dense and somewhat run-on in the middle ('the table that defines it, the table it points to for reference and list fields'), which slightly hurts scanability but not clarity.

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 moderately complex describe tool with an output schema, the description covers what is returned, what is conditionally returned, what is filtered out, and how caching interacts with the result. Remaining gaps, such as the effect of the 'fields' filter on the returned structure, are adequately covered by the schema.

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 all four parameters are already documented in the schema. The description adds no additional meaning for the 'fields', 'refresh', or 'instance' arguments, so it sits at the baseline for a fully described schema.

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 opens with a specific verb and resource ('List the fields of a table from the instance dictionary') and immediately scopes it by naming inheritance and the concrete example 'task for incident'. That is enough to distinguish it from data-fetching siblings like request_table or request_tables 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?

It gives a clear trigger: 'Use it before querying a table whose fields you do not know for sure, custom application tables included.' It does not name an alternative tool or state when not to use it, so it stops short of full routing guidance.

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