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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuine behavioral context beyond that: the exact subject matter compared and an explicit NOT-a-fit list (no patient records, LIMS, SMS, payroll), which tells the agent what the answer will and won't address. No return format or length/pagination notes, but those matter little for a static informational tool.

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 core function is front-loaded in the first clause, with the comparison dimensions and exclusions compactly listed and the usage trigger placed last. It is dense but every element (replaces/interplay/cost/non-fit) earns its place; only the packed colon list slightly reduces readability.

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?

For a zero-parameter, read-only informational tool with no output schema, the description supplies what an agent needs: what the comparison contains, who it's for, and what it explicitly does not cover. The only omission is disambiguation from the cost-oriented get_pricing sibling, which keeps it short of a 5.

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 tool takes zero parameters, so there is nothing for the description to clarify beyond the schema; the baseline for a no-param tool is 4.

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 opens with a specific verb and scope ('Explains how oqda differs from running separate tools') and enumerates what the comparison covers: feature replacements, module interplay, cost, and non-fit areas. It is clearly distinguishable from informational siblings like list_modules, though the 'what it costs' coverage overlaps with get_pricing without acknowledging that sibling.

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?

It gives an explicit trigger: 'Use it when a user asks for alternatives or whether oqda suits them,' which is concrete and actionable. It does not name or exclude any sibling tool (e.g., when to prefer get_pricing over this), so routing is clear but not fully disambiguated.

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