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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds the useful nuance that inspection surfaces provenance and freshness metadata plus a bounded sample, but it does not mention that sampling only applies to queryable sources or what happens for non-queryable ones.

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?

A single front-loaded sentence with zero filler; the four inspected facets are packed efficiently. It is arguably too terse for a tool with a nested input object, but nothing in it is wasted.

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?

With no output schema, the description does the minimum by enumerating what is returned (schema, provenance, freshness, sample). It omits when to prefer this over other read tools and any caveats about sources that are not queryable, leaving meaningful gaps for a two-parameter nested-input tool.

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?

The schema itself carries strong descriptions for both parameters (namespaced sourceId format, sampleRows default 5 / max 20 / 'use 0 for schema-only inspection'). The description's phrase 'a small sample of features' is consistent with that but adds no syntax or behavioral detail the schema lacks.

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 uses a specific verb ('Inspect') and enumerates the concrete facets returned: attribute schema, provenance, freshness, and sample features. That clearly separates it from sibling mutators like source_update_metadata or source_import_url, though it does not explicitly name a sibling alternative.

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 statement of when to call this versus alternatives such as project_query_database, resource_view, or source_update_metadata. The agent must infer from the name that this is a pre-flight/preview inspection step, which is exactly the guidance the description should supply.

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