brc_update_purchase

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

With no annotations, the description fully bears the burden of behavioral disclosure. It transparently explains the preflight/confirmation workflow and what the first call returns (confirmation_required and payload preview). However, it does not mention any side effects or permission requirements, though the confirmation pattern mitigates risk.

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 two sentences and front-loads the purpose. The second sentence is dense but packs essential workflow instructions. No extraneous words; could be slightly clearer by breaking into steps, but overall efficient.

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?

Given the tool has 15 parameters, no output schema, and low schema coverage, the description focuses on the critical confirmation pattern but omits details about what updates are possible (e.g., which fields can be changed) and return values. It provides enough for correct invocation but not full contextual completeness.

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 low (20%) and the description adds meaningful context for the confirmWrite parameter only, explaining its role in the workflow. Other parameters are not individually described beyond what the schema provides. This partially compensates for the low coverage but leaves many parameters undocumented.

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 clearly states it 'Updates a BRC purchase', which is a specific verb and resource. While it doesn't list the specific updatable fields, the purpose is unambiguous and distinguishes it from siblings like brc_create_purchase or brc_get_purchase.

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 description provides explicit two-step instructions: first call without confirmWrite to get a preview, then retry with confirmWrite=true only after explicit user confirmation. It also warns that 'Passing preflight is not confirmation,' offering clear guidance on when and how to use the tool compared to alternatives.

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