Describe a topic in a data source

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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description adds useful behavior details: the output includes a short summary, DuckDB schema, IDL definition, and SQL guidelines, while excluding actual data. This enriches the agent's understanding without contradicting annotations.

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 description is two sentences, front-loaded with the action and immediately followed by a concise list of includes/excludes. Every word contributes value; no filler or redundancy.

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?

The tool is relatively simple (read-only metadata fetch) and the output schema exists. The description covers what the output contains (summary, schema, IDL, SQL guidelines) and what it excludes (actual data). The only gap is parameter semantics, but overall the description is complete enough for an agent to invoke correctly with reasonable assumptions.

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%, and the description does not explain any of the parameters (path, topic, args). The names are somewhat self-explanatory (path likely refers to data source path, topic to topic name), but the description provides no explicit guidance on their format, constraints, or relationships. The agent must rely solely on schema field names, which is insufficient for a 0% coverage situation.

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 clearly states 'Generate a structured summary of a topic' with a specific verb and resource, and explicitly lists inclusions and exclusions. It distinguishes from siblings like query_messages (which returns messages) and describe_data_source (which describes the entire source, not a topic).

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?

The description clarifies it does not return messages, implying it's for metadata/schema when querying topics. However, it does not explicitly name alternative tools for when to use them or provide positive guidance on when to choose this tool over peers like describe_data_source or query_messages. The context is clear but lacks explicit alternatives.

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