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

Annotations already declare readOnly=false, idempotent=false, destructive=false and openWorld=false, so the safety profile is covered. The description adds a genuine behavioral detail — a link passed as the step becomes an openable step — but says nothing about what happens if the routine is not an open list or does not exist.

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 short sentences, front-loaded with the action and its scope constraint, with no padding. The second sentence is tersely phrased but does carry signal rather than 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 3-parameter, non-destructive write with full schema coverage and no output schema, the essentials are there, but the description omits what happens on invalid/non-list routines and how this differs concretely from add_note in the same family.

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 baseline would be 3, but the description adds real meaning beyond the schema: the 'link becomes a step that opens it' sentence explains the link-handling semantics of the 'title' parameter. 'detail' remains unexplained in the description, keeping it off a 5.

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 ('Adds a step to a routine') plus the scope constraint that the routine stays open as a list, with concrete examples (Inbox, To read). It implicitly separates itself from run-oriented siblings like start_run or next_step, though it never names them.

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 'stays open as a list' qualifier hints at when this applies, and the title examples help, but there is no explicit when-to-use guidance, no named alternative (e.g. add_note vs this), and no stated precondition or failure behavior.

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