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

Annotations already declare readOnlyHint=true/destructiveHint=false, so the safety bar is lower, yet the description adds real behavioral context: results are ordered newest first, pagination is cursor-based via next_cursor, and it requires the user's Cotlet API key with app access. Missing only a note on result-set limits or default window behavior.

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?

Front-loaded with the resource and its returned fields, then filters, then ordering/pagination, then the auth requirement — a sensible order. Slightly repetitive in re-stating "the same filters as the Transactions page" twice, but overall tight for the amount of information conveyed.

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 9 optional parameters, no output schema and no required params, the description supplies what the schema cannot: ordering, cursor pagination, auth requirement, and the set of filterable dimensions. It stops short of describing what fields each result contains beyond the four named, but is adequate for a read-only list tool.

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 the baseline is 3 and the schema already documents every filter. The description restates the filter list (customer email, offer, transaction type, date range, country, customer type) with no added syntax, defaults or format detail, so it adds marginal value over structured data.

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 ("Lists transactions") and enumerates the fields surfaced (customer, offer, amount, transaction type). An agent can identify the operation, but the description never distinguishes it from siblings like systeme-io_export_transactions or systeme-io_get_transaction, which a listing tool in a family of four transaction tools should do.

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?

"Lists transactions with the same filters as the Transactions page" implies the browse/query use case, and the cursor sentence gives concrete pagination guidance. However there is no explicit when-to-use vs. when-to-use-alternatives guidance (e.g., use export_transactions for bulk download, get_transaction for a single record), which is the main ambiguity for this tool.

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