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

Annotations already cover readOnlyHint, idempotentHint and openWorldHint, so the safety profile is known. The description adds genuine disclosure the annotations don't: the ledger shows only verified deals and never exposes private floors, fees, or contact details — exactly the kind of data-exposure context an agent needs before surfacing results. It stops short of describing pagination/result-size behavior, which the schema partly covers via limit/cursor.

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?

The description is short and front-loaded, with the WHEN trigger and the privacy guarantee early. The trailing 'Example: barter_ledger {}' is low-value filler for a tool with zero required parameters, but it consumes little space.

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?

There is no output schema, so the description must explain what comes back — and it does, enumerating the deal fields and the House Verified marker. Combined with full schema coverage on inputs and read-only annotations, an agent has what it needs to call this correctly; only guidance on pending vs completed offers against siblings is missing.

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% — limit, cursor and handle are all documented in the schema, so the baseline applies. The description adds indirect meaning by listing the returned fields, which clarifies what 'handle' filters on (seller or buyer), but it never mentions the parameters directly.

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 names the resource and its scope precisely: a public ledger of completed cash barter and swap deals, plus the exact fields returned (date, seller, buyer, item, price/swaps description, House Verified). The word 'completed' implicitly separates it from open-offer siblings such as barter_list and barter_offers, but no sibling is named explicitly.

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 'WHEN:' clause gives a usable trigger condition ('public ledger of completed ... deals'), which is enough to know when to reach for it. There are no explicit exclusions or pointers to sibling tools for open/pending offers, so the agent must infer the boundary between this and barter_list or barter_offers.

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