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

readOnlyHint=true already establishes the safe-read profile, so the description is not carrying that burden. It adds meaningful behavioral context by naming the exact payload contents (tickets, receipts, refunds, line items, billing address, payment details) and the underlying GET endpoint, telling the agent this is a rich single-object fetch with no side effects.

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?

Two tight sentences that front-load the operation and its return contents. The trailing API-endpoint mapping is marginally redundant given the tool name and schema, but it is short and aids cross-referencing with the upstream API.

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?

With no output schema, the description compensates by enumerating the registration payload contents, and readOnlyHint covers safety. For a simple 3-parameter read tool this is essentially complete, though it omits any note on error cases (e.g. unknown slug) or auth scoping beyond the schema.

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 description coverage is 100%, so all three parameters are already documented in the schema, including slug formats and the optional account_slug fallback. The description restates the slug example ('reg_...') but adds no syntax or semantics beyond the schema, so baseline 3 applies.

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?

States a specific verb and resource ('Fetch a single registration (order) by slug') and enumerates the returned sub-resources (tickets, receipts, refunds, line items, billing address, payment details). This clearly separates it from the sibling tito_list_registrations, which returns many.

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?

Usage is implied by 'single registration by slug' versus the list sibling, and the required slug format signals when it applies. However, there is no explicit when-to-use/when-not guidance or named alternative, so routing is left to inference.

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