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

The annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered structurally. The description adds genuine value by telling the agent what information the records contain (pricing basis, denied capabilities, validation status), but says nothing about result volume, pagination, or how 'denied capabilities' are represented.

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 tight sentence that front-loads the verb and resource and packs the returned attributes efficiently. The trailing list of attributes is dense but each item carries information, so nothing is wasted.

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 read-only catalog listing this is close to adequate: the annotations cover the safety profile and the description enumerates what each record contains. However, the sole filter parameter is undocumented in both schema and description, and there is no hint about result size or pagination, leaving a real gap for an agent that needs to enumerate the full catalog.

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 single parameter 'category' has an enum and a default of 'all', but zero schema description coverage, and the description never mentions filtering by category at all. With coverage at 0% on a non-trivial enum parameter, the description should compensate and does not; an agent cannot tell whether 'category' scopes the listing or is merely a tag.

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 ('List') and resource ('Codex Immortal products and services') and even enumerates the attributes surfaced (pricing basis, capabilities, denied capabilities, validation status). It implicitly distinguishes itself from the singular sibling codex_catalog_get_product, though it never names that sibling or states the distinction explicitly.

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?

There is no when-to-use guidance, no when-not-to-use guidance, and no mention of alternatives such as codex_catalog_get_product for single-item lookups or codex_quote_request for pricing. The agent is left to infer all routing from the tool name alone.

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