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

readOnlyHint=true already covers the safety profile. The description adds genuinely new information — that filters are conjunctive and how pagination continues via next_page — plus the underlying endpoint. It doesn't disclose default ordering or result shape, so it adds value but not rich behavioral context.

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 short sentences, each carrying distinct information: purpose, filter composition, pagination. Front-loaded with the core action and zero filler.

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 simple, fully-documented, read-only list tool with five optional parameters, the description covers purpose, filtering semantics and pagination. With no output schema, a brief note on what the response contains (or that next_page is returned) would close the last gap.

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 the baseline is 3, but the description adds real semantics beyond the schema by stating that filters combine with AND — something an agent cannot infer from the individual parameter definitions. The paging note on next_page is somewhat redundant with the schema's page description.

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 gives a specific verb ('List or search') and resource ('payment transactions recorded on invoices'), which is clearly distinguishable from the singular sibling halaxy_get_payment_transaction. It doesn't explicitly name that sibling, but the scope of the operation is unambiguous.

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 explains the search context ('filters combine with AND') and the paging contract ('pass next_page as page'), which tells an agent how to chain calls. It stops short of explicit exclusions or naming halaxy_get_payment_transaction as the single-record alternative.

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