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

No annotations are present, so the description carries the behavioral burden. It does disclose that this is a fetch operation and that paging metadata is returned, but it does not specify the shape of that metadata, the terminal pagination condition, or behavior for invalid or missing block IDs.

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?

Two sentences with no filler. The core action is front-loaded, and the pagination guidance follows immediately.

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 simple three-parameter read tool without annotations or an output schema, the description supplies purpose, pagination strategy, and the existence of paging metadata. It stops short of documenting the paging metadata fields or the end-of-pagination signal, which would make it fully self-contained.

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%, so the schema already documents block_id, offset, and limit with defaults. The description reinforces the offset/limit pagination usage but adds no information beyond what the schema provides.

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 action and resource: fetch a slice of a block's content. The qualifier 'for large blocks' and the focus on pagination distinguish it from list_blocks or get_block_history without ambiguity.

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?

Clearly explains how to use offset/limit to paginate and signals that the tool is intended for large blocks. It does not name an alternative tool or give an explicit when-not-to-use condition, so it falls slightly short of full usage routing guidance.

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