get_selection_data

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

With no annotations provided, the description carries the full burden. It discloses the output format (CSV), the role of selection_code (required) and max_rows (optional limit), and warns about large tables. No side effects or destructive behavior are expected, and the description is consistent with the tool's read-only nature.

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 concise (3 sentences plus an Args section) and front-loaded with the main purpose. Every sentence adds value: purpose, prominence, how to find selection codes, and parameter details. No fluff 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 has 2 simple parameters and an output schema (not shown). The description explains the output format, primary usage, and necessary prerequisites (selection codes). It omits potential error handling or rate limits, but given the low complexity and presence of an output schema, the description is sufficiently complete for an agent to 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?

The input schema has 0% description coverage (only titles), but the description adds detailed meaning: selection_code is exemplified as 'CEN0101HT01', and max_rows is explained with its default (100) and the caution 'Set to 0 for unlimited (use with caution — some tables are very large).' This fully compensates for the schema's lack of description.

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 purpose: 'Fetch actual statistical data from a predefined selection as CSV.' It uses a specific verb ('Fetch') and resource ('statistical data from selection'), and distinguishes itself as 'the primary and most reliable way to get data,' implying prioritization over sibling tools like get_value or custom_query.

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 context on when to use this tool: it is the primary way to get data, and guides the user to find selection codes using search_selections() or get_dataset_selections(). It also includes a caution about using max_rows=0 for large tables. However, it does not explicitly state when not to use this tool versus alternatives like custom_query.

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