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

Annotations already declare readOnly=true, destructive=false, openWorld=true, so the safety profile is covered. The description adds genuine value by disclosing that the response embeds allocations to invoices, but says nothing about what happens for a missing id or how large the allocation set can be.

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 front-loaded sentence with the payload detail first, followed by the REST endpoint for agents that reason about API shape. No filler, though the endpoint path is marginal for an MCP consumer.

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?

A single-parameter read tool with full annotations needs little, and the description covers the key return element (allocations). With no output schema, however, the remaining payment fields and not-found behavior are left undisclosed.

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 already documents payment_id as an inv.bg payment id sourced from invbg_list_payments. The description only restates 'by id', adding nothing beyond the schema, which is the expected baseline.

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 ('One payment by id') and adds scope detail that the payment carries its invoice allocations (invoice_payments). This clearly separates it from invbg_list_payments by singular-vs-list, though the sibling is never named.

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?

No explicit guidance on when to use this versus invbg_list_payments or invbg_get_invoice; the only routing hint ('invbg_list_payments') lives in the parameter schema, not the description. Usage is inferable from 'by id' but never stated.

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