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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds a genuine behavioral nuance beyond structured data: supplying a customer or vendor causes the date filter to be ignored, which an agent would otherwise get wrong. Return format is partially described (account number, name, balance), but pagination behavior is left to the schema.

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 covers what the tool returns and every filter, with the account-group legend parenthetically embedded. No filler, and the most important information (record, fiscal year, returned fields) comes first.

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 10 parameters, 100% schema coverage, and annotations carrying the safety profile, the description supplies the missing semantic layer (account-group legend, date-override rule) and names the returned columns. No output schema exists, but the returned fields are listed, so nothing critical is absent.

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%, establishing a baseline of 3, but the description adds real meaning the schema lacks: it decodes the account_group values (1 other, 2 fixed assets, 3 bank/cash, … 14 non-deductible expenses) where the schema only says '1-14'. It also restates the customer/vendor-overrides-date interaction that affects parameter precedence.

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 ('Account balances from the Collmex accounting (record ACCBAL_GET) for a fiscal year') and enumerates the returned fields (account number, name, balance). The resource is clearly distinct from siblings like collmex_list_invoices or collmex_list_open_items, though it never explicitly contrasts with them.

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?

Enumerates the available filters (account, account group, cost centre, date, customer/vendor), which implies how to narrow results, and notes that customer/vendor cause the date to be ignored. However it never says when this tool is preferable to siblings such as collmex_list_accounting_documents or collmex_list_open_items, so routing still requires inference.

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