Plane MCP

update_cycle

Update a cycle by providing only the fields to change: name, start/end dates, description, or project. Unspecified fields remain unchanged.

Instructions

Update a cycle. Only provided fields change.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "cycle_id": "<cycle_id>"
    },
    "name": "update_cycle"
  }
}

Input Schema

Name	Required	Description	Default
`name`	No
`cycle_id`	Yes
`end_date`	No
`project_id`	No
`start_date`	No
`description`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 6, 2026

TDQS

C2.8/5.0

Behavior2/5

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does disclose the partial-update behavior, but leaves many questions unanswered: error handling for non-existent cycles, whether null values clear fields, permission requirements, and response format. This is insufficient for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two short sentences with no redundant words. It effectively front-loads the action and adds a single key behavioral caveat. Every word earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Despite having an output schema, the tool has six parameters and no annotations. The description fails to provide usage guidance, parameter semantics, or error behavior, leaving significant gaps for correct invocation. It is not complete for a tool with this complexity.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

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 by explaining parameters. The statement 'Only provided fields change' gives a general rule but does not clarify the meaning of individual fields like project_id or start_date, nor the treatment of explicit null values (clear vs ignore). This creates ambiguity for the agent.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses the specific verb 'Update' with the resource 'a cycle', clearly identifying the action. The added clause 'Only provided fields change' distinguishes it from a full replacement update, though it doesn't explicitly compare to sibling tools. Overall, purpose is clear but not maximally differentiated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus sibling tools like create_cycle or set_work_item_status. It doesn't state prerequisites, such as the cycle existing, nor does it suggest alternatives. Usage is only implied by the tool name.

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