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

Beyond the read-only annotations, it discloses meaningful behavior: the result is a standalone record and using it as a subject narrows a pipeline step to the selected stretch. It does not describe edge cases such as behavior when nothing is selected, but the annotations and output schema already cover safety and return shape.

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, front-loads what the tool returns, and immediately explains the practical consequence. Every sentence adds useful information with no repetition or filler.

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 read-only getter with a full input schema and an output schema, the description supplies the essential purpose and pipeline usage context. It leaves minor gaps around no-selection behavior and sibling choice, but nothing critical to invoking the tool.

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%, so pad and reverse_complement are already fully documented in the input schema. The description adds no parameter-specific meaning beyond the schema, which is the expected baseline when the schema does the heavy lifting.

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 identifies the resource: the canvas-selected region returned as its own record. It explains the distinctive role of that record as a pipeline input, though it does not explicitly contrast this tool with siblings such as browse_region or get_open_record.

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?

It gives a concrete usage pattern: wire the returned record into a node's subject so that the step runs on the selection instead of the whole molecule. It does not state when not to use it or name alternative tools, so it falls short of full when/when-not/alternatives guidance.

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