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

While annotations already set destructiveHint=true, the description adds crucial behavioral specifics: the final 'confirm' answer creates a REAL order and requires explicit user approval. It also explains the stateful nature (call repeatedly, answer one question at a time), which is not apparent from annotations alone. No contradiction with 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?

Three tightly packed sentences deliver the fallback use case, alternative tools, stateful flow, and critical safety warning. Every sentence serves a distinct purpose with zero redundancy, and the most critical information (fallback + alternatives) is front-loaded.

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?

It covers the essential flow: first call empty, stateful progression, completion status, and destructive final action. It could elaborate on error handling or the nature of the questions, and the output schema existence mitigates the need for return-value details. Minor gaps remain but the description is largely complete for a complex stateful wizard.

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%, so all parameters already have descriptions. The description merely restates 'First call: empty arguments' and 'same session_token', which are also in the schema. It adds no new semantic meaning beyond what the schema provides, meeting the baseline for high schema coverage.

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 explicitly states it is a 'Text-only fallback purchase flow for clients WITHOUT widget support' and directly contrasts it with list_esim_plans / list_products + validate_order + create_order, making the purpose and resource unmistakable and clearly distinguishing it from sibling tools.

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 explicit when-to-use context ('for clients WITHOUT widget support') and when-not-to-use ('In ChatGPT prefer ... instead'), listing the preferred alternatives. It also details the stateful interaction pattern: repeated calls with the same session_token, answering one question at a time until status is 'complete', with first-call behavior specified.

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