get_facts

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully disclosed. The description adds behavioral context by stating the facts table includes source URLs and verification dates, which informs the agent of exactly what the response will contain. No contradiction exists.

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 a single paragraph that front-loads the core purpose ('Return the full IRS-sourced facts table'), then lists contents, then gives a use case, and ends with a redundant 'takes no arguments.' Every sentence serves a purpose, and the structure is efficient.

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 tool is parameterless and read-only, the description covers all essential aspects: what data is returned (contribution limits, RMD rules, rollover rules, early distribution tax/exceptions), additional metadata (source URL and verification date), and the intended use. No output schema exists, so the description is the primary documentation, and it is sufficient for an agent to select and invoke the tool 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 schema has zero parameters, so the baseline is 4. The description's note 'Takes no arguments' adds no new information but is consistent. Since there are no params, the description appropriately does not need to compensate for schema gaps.

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 states a specific verb 'return' and resource 'full IRS-sourced facts table the checker verifies against,' clearly distinguishing it from the sibling check_answer which presumably verifies answers. It also enumerates the specific content types, leaving no ambiguity about the tool's function.

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 gives explicit guidance on when to use it: 'Use it to show a reviewer why a number was flagged,' implying it is for retrieval and justification, not for verification itself. Since the only sibling is check_answer, the context makes the division of labor clear, though it does not explicitly state 'use check_answer for verification.'

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