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

Annotations already declare destructiveHint=true and idempotentHint=true, so "Replace the list" adds little on safety. But the description adds real behavioral context beyond the annotations: routines materialize as plan items from today onward, and passing existing ids preserves them. It does not state what happens to routines omitted from the new list.

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?

Front-loads the core purpose in the first clause, then packs workflow, defaults, and id semantics into a few dense sentences. Every sentence carries information, though the flow jumps between workflow, defaults, and id handling without clear ordering.

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 destructive, idempotent replace of a nested list with no output schema, the description covers the key agent needs: side effects (plan items created), id preservation, days encoding and default, and related tools. Still gaps on what removal of existing routines means for already-generated plan items.

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 0%, so the description must compensate. It does well for the two non-obvious fields: "days are ISO weekdays 1=Mon..7=Sun, default every day" and "Pass existing ids to keep them." But area, title, leverId, projectId, and estimateMin are left to the schema, so compensation is only partial.

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 ("Replace the list of routines") and immediately clarifies what a routine is ("small steps that repeat on fixed weekdays"). It also names the sibling tools that interact with the resulting items (edit_plan_item, delete_plan_item, set_plan), so an agent can place it among alternatives.

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?

Explains the downstream workflow clearly: tick with edit_plan_item, skip a day with delete_plan_item, and that set_plan preserves them. However it never states the prerequisite for calling this tool directly (e.g. when to use set_routines vs get_routines, or that it overwrites the whole list), leaving some inference.

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