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

Annotations only indicate readOnly=false and destructive=false, so the description carries the burden of explaining mutation behavior. It clearly discloses the non-obvious replace semantics of assigned_to and the 'same project' constraint for epic_id, adding meaningful context beyond annotations.

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 front-loaded with the primary purpose, then organized by operation. Every sentence adds necessary behavioral or prerequisite information without unnecessary filler, and the critical exception is highlighted with an uppercase emphasis.

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 mutation tool with no output schema and annotations that don't disclose effects, the description covers the essential behavioral rules, prerequisites, and id source. It does not describe the return value or possible errors, but those are less critical given the clear operational scope.

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 parameters are already documented. The description adds key semantic detail beyond the schema: epic_id must belong to the same project, assigned_to REPLACES all assignees with [] clearing, and unspecified fields remain unchanged. This improves an agent's ability to call the tool correctly.

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?

Description uses a specific verb and resource ('Update a roadmap slot') and immediately enumerates the allowed operations: reschedule/resize dates, move to another epic, and set assignees. This clearly distinguishes it from create_roadmap_slot and delete_roadmap_slot among siblings.

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?

Provides explicit operational guidance: 'Only supplied fields change', warns that assigned_to replaces the full assignee set, advises reading the slot first, and notes the Pro/trial workspace requirement. It does not explicitly contrast with alternative update tools, but the update semantics are unambiguous enough.

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