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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered. The description adds useful content context (USD, one-time vs monthly, what's included/excluded), but that is return-content detail rather than behavior beyond 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?

One compact sentence, front-loaded with the resource and scope, ending with the invocation rule. Every clause earns its place with no filler.

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 single optional-param, read-only lookup with full schema coverage, the definition covers purpose, scope, and the omit-parameter behavior. With no output schema, the description helpfully sketches return contents. Minor gap: it doesn't state whether results are ordered or grouped, but nothing essential is missing.

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 coverage is 100% and the single param already carries its own description, so the baseline is 3. The description adds genuine semantic value by explaining the default behavior when plan_id is omitted ('get everything'), which the schema does not state.

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?

Specific verb+resource ('get_pricing' return contents) with a precise enumeration of what is returned: public plans and add-ons, USD prices, one-time and monthly, inclusions/exclusions, and the purchase page. Clearly distinguishable from siblings like list_services or get_contact_options, which cover different resources.

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?

States the key invocation rule explicitly: 'Omit plan_id to get everything.' This tells the agent how to get all data vs a single filtered item. No exclusions or alternative tools are named, but the sibling set covers unrelated domains so no routing conflict exists.

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