get_reverse_charge_rules

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

With no annotations, the description carries the full burden. It does hint at the return content by saying it 'explains when and how to apply' reverse charge, which tells the agent this is explanatory reference material rather than a lookup of a specific rate. It still omits scope (all member states? exceptions?), currency/jurisdiction limits, and whether the data is static or dated.

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?

Two short sentences, purpose first, with no padding or boilerplate. The second sentence ('Explains when and how to apply reverse charge') is only marginally additive over the first, which keeps it just short of a 5.

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 zero-parameter, no-output-schema reference tool this covers the essentials, but it is thin on the details an agent needs to trust the result: geographic coverage, whether the rules are current/versioned, and how it relates to the sibling OSS and VAT-rate tools.

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 tool takes zero parameters, so there is nothing for the description to clarify; baseline 4 applies. The absence of any filtering arguments is consistent with the description's implication that it returns a general rule set rather than a per-transaction answer.

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 ('Get') and a well-defined resource ('reverse charge mechanism rules') scoped to EU cross-border transactions, plus a note on what the content covers. It is clear against most siblings, though it never explicitly distinguishes itself from the adjacent get_oss_rules or get_vat_rates tools.

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?

The phrase 'for EU cross-border transactions' implies the scenario in which this tool applies, which is more than nothing. However, there are no when-not conditions, no mention of prerequisites, and no routing to or away from the many sibling rule tools.

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