Read Database Columns

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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, fully describing the safe, non-mutating behavior. The description adds minor behavioral context (reads schema metadata, useful for empty databases) but does not go beyond what annotations imply. It does not contradict annotations, so score is appropriate baseline.

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: the first delivers the core purpose, the second adds a specific use-case context. Every sentence is informative and non-redundant, with no wasted words. It is front-loaded and easy to parse.

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?

Given the simple read-only nature, rich annotations, and full schema coverage, the description adequately conveys the tool's function and when it is useful. It mentions the returned data (columns, select options, mappings), compensating for the lack of an output schema. It is sufficiently complete for an agent to select and invoke correctly.

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 each parameter (docId, workspaceId, databaseBlockId) already has a clear description in the schema. The tool description does not provide additional parameter-level information, such as format or constraints. Per rubric, baseline is 3 when coverage exceeds 80%.

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 the verb 'Read' and the resource 'schema metadata for an AFFiNE database block', specifying included elements (columns, select options, view column mappings). This distinguishes it from sibling tools like 'read_database_cells' (reads cell values) and 'add_database_column' (adds a column), making purpose unambiguous.

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 provides clear context by stating 'Useful for empty databases before any rows exist,' indicating a specific scenario. However, it does not explicitly exclude alternatives or mention when not to use this tool, such as when column metadata is not needed or when rows exist. The guidance is helpful but lacks explicit comparisons to siblings.

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