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

Annotations already declare openWorldHint=true and destructiveHint=false, so the description's job is to add operational context, which it does: automatic best-tool selection, time cost scaling with hardness and tool, and drops landing directly in inventory. That tells the agent this is a time-consuming, self-contained action rather than an instant read, though it omits failure modes (unbreakable blocks, missing tools).

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?

Four short sentences with the reach constraint front-loaded and zero filler. Slightly more could have been trimmed, but nothing is redundant with the name alone.

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 usefully pre-empts the return-value question by stating drops go straight to inventory, and it flags latency. What's missing is the reach/precondition detail that determines whether a call will succeed, but the core call semantics are covered.

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% and every parameter (x, y, z, api_key) is documented inline, so the baseline applies. The description adds no coordinate formatting or range guidance beyond the schema's own min/max bounds.

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 and resource ('Break a block') plus a hard operational bound ('within 4.5 blocks'), which immediately separates it from siblings like place, attack, or use. It does not name a sibling explicitly, so the differentiation is inferential rather than stated.

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 4.5-block reach constraint implies you must already be adjacent to the target, but the description never says so as a precondition or points to goto/move when out of range. No explicit when-not or alternative routing is provided.

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