Get Hmrc Vat Obligations

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds useful context beyond that: the data comes from an external authoritative source (HMRC MTD), the exact shape of returned obligations, and the connectivity requirement. No contradiction between description and annotations.

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 sentences, each earning its place: the first states core function and output content, the second gives usage triggers, the third states the prerequisite. The core function is front-loaded, and the entire description is roughly 55 words with zero fluff or repetition of schema details.

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 moderate-complexity tool with no output schema, the description adequately covers what is returned (period keys, dates, fulfillment status), the external source, and the prerequisite. Annotations cover the safety and idempotency profile. A minor gap is that it doesn't hint at checking HMRC MTD connectivity first (e.g., via the sibling tool get_integration_status), nor does it address error behavior if unconnected.

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%: both 'from' and 'to' parameters already have descriptions specifying format (YYYY-MM-DD) and defaults in the schema. The description does not add parameter-level meaning beyond what the schema already provides. Since the schema carries the full burden, the baseline of 3 is appropriate.

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 uses a specific verb ('Read') with a precise resource ('VAT obligations ... directly from HMRC MTD') and enumerates the exact data fields (period keys, start/end dates, due dates, Open/Fulfilled status). This clearly distinguishes it from siblings like get_hmrc_vat_payments and get_hmrc_vat_liabilities, which concern different data types.

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?

Three concrete trigger phrasings are provided ('what does HMRC say I owe a return for', 'when is my next VAT return due according to HMRC', 'reconcile our periods against HMRC's record'), which give the agent clear conditions for selection. The prerequisite ('Requires HMRC MTD connected') is stated. However, alternatives are not named explicitly, and there is no when-not-to-use guidance against similar siblings like get_vat_periods.

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