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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds nothing beyond that — no note on whether it performs a network round-trip to a live DataStore, what happens with an invalid or unknown resource_id, or what shape the returned field schema takes. With annotations present the bar is lower, but this contributes zero extra context.

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?

One short, front-loaded sentence with no filler — but it is concise to the point of under-specification rather than efficiency, so it sits at minimum viable.

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, so the description is the only place to convey what a "field schema" return looks like (column names, types, nullable flags), and it does not. Combined with an unexplained required identifier and no sibling routing, an agent lacks enough to call this confidently in the right situations.

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 0% for the single parameter resource_id, and the description does not compensate: it never says what a resource is, where the identifier comes from, or whether it is a DataStore resource slug versus a dataset-level identifier. For a 1-param tool the burden falls squarely on the description, and it is not met.

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 verb ("Return") and a specific resource ("DataStore field schema for a resource"), so an agent knows exactly what comes back. It does not differentiate from siblings like istanbul_query_resource or istanbul_get_dataset, which the rubric caps at 4.

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?

There is no guidance on when to call this versus istanbul_query_resource, istanbul_get_dataset, or istanbul_search_datasets, and no prerequisite stated (e.g. that resource_id must first be obtained from a dataset listing). The agent must infer the workflow entirely.

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