xpayr_get_payment_session

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

With no annotations at all, the description carries the full behavioral burden. 'Retrieve' implies a safe read and the field list signals a rich payload, but it says nothing about authentication/merchant scoping, what happens with an unknown or expired session_id, or any rate limits.

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 tightly packed sentence that front-loads the verb and resource and then lists the substantive return payload. No filler or redundancy.

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?

There is no output schema, so the enumeration of returned fields is exactly the compensation needed, and for a single-parameter read tool that is nearly sufficient. Missing only auth/error context, which keeps it short of full completeness.

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 session_id parameter is already fully documented by the schema at 100% coverage, including the 'ps_...' format example. The description adds no additional meaning about the parameter, so the baseline of 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?

The description uses a specific verb ('Retrieve') plus a precise resource ('a specific XPayr payment session') and enumerates what is returned (metadata, settlement split amounts, checkout mode, on-chain transaction hash). It implicitly separates itself from list_payment_sessions by scoping to a single session, but never names or contrasts a sibling such as get_public_payment_status.

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 only implied: an agent can infer this is the per-session lookup tool, distinct from the listing tool. There is no explicit statement of when to prefer it over xpayr_get_public_payment_status, nor any prerequisite or exclusion guidance.

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