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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description usefully adds the emitted output shape and the pipeline-wiring contract, but says nothing about what happens when no record is open or what conditions cause failure — a meaningful gap for a state-dependent tool.

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 dense sentences, front-loaded with the purpose and followed immediately by the consumption contract. No filler, no restatement of the tool name.

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 an output schema present and annotations covering safety, the description need not explain return values, and it correctly focuses on purpose and wiring. Only the empty-state/error behavior when no record is open is unaddressed.

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% and the nested _subject/_files shapes are documented in the schema itself; the description adds no syntax, format, or constraint detail beyond that. Baseline 3 is appropriate when the schema carries all parameter meaning.

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 — 'Return the plasmid/sequence currently open in the editor' — which is more precise than a generic fetch. The 'currently open in the editor' scope implicitly separates it from fetch_record/load_record, but no sibling is named explicitly, so an agent still has to infer the distinction.

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 gives real pipeline usage guidance ('it is the SOURCE node of a pipeline — wire its record into any downstream node's $subject'), which tells the agent how to consume the output. However, it offers no when-not guidance and never contrasts with siblings like load_record, fetch_record, or get_selection, so alternative selection is left implicit.

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