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

Goes well beyond the annotations: a size change restarts a running briq and its processes start over, stopped/sleeping briqs apply it at next start, volume only grows and does so without restart under a running briq. It also discloses validation ('sizes, disk and credits') and the async landing window with the `resizing` state — consistent with destructiveHint=false and idempotentHint=true.

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?

Front-loaded with the action and the data-retention guarantee, then example, then restart semantics, then return behavior — a sensible agent-reading order. Every sentence carries distinct information; nothing is restated from the schema or annotations verbatim.

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 no output schema, the description covers return behavior itself ('returns once it lands, up to 30 s; `resizing` means still on its way'), plus restart risk, validation, and partial-failure signaling — everything needed to call and interpret this correctly.

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 67%, and the description compensates by naming both optional knobs semantically ('another size', 'bigger volume') and giving a concrete call example with size and volumeGb. It adds the growth-only constraint on volume, though it does not restate the allowed size enum or the 1-500 GB bound, which remain schema-only.

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 (resize) and resource (briq), and immediately pins the scope by contrasting with the alternatives: 'keep the briq: its disk, volume and URLs stay' implicitly distinguishes it from briq_fork and briq_up. An agent can tell what this does without opening the schema.

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 retention clause ('its disk, volume and URLs stay') gives a clear condition for choosing resize over fork/recreate, and the volume-growth rule tells you when volumeGb is applicable. It never explicitly names a sibling to use instead or states when not to use it, so it stops short of full routing guidance.

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