io.github.Lynn-hh/armguard-mcp

Overview Schema Source Related Servers Discussions Admin

plan_to_pose

Read-only

Plans a non-executing joint-space motion to bring the TCP to a target pose via inverse kinematics; returns a summary validated against the safety envelope.

Instructions

Plan (do NOT move) a motion that brings the TCP to a pose. Uses inverse kinematics; the path is a joint-space interpolation (the TCP does not move in a straight line - use plan_cartesian_path for that). Returns a plan summary validated against the safety envelope.

Input Schema

Name	Required	Description
`frame_id`	No	Frame of the target; default = robot base frame
`position`	Yes	Target TCP position [m]
`orientation`	No	Target TCP orientation (x, y, z, w); omit to keep current
`velocity_scaling`	No	Fraction of max joint speed (0, 1]
`acceleration_scaling`	No	Fraction of max joint accel (0, 1]

Output Schema

Name	Required	Description
`kind`	Yes
`notes`	No
`status`	Yes	rejected plans can never be executed; needs_approval requires a human to approve
`dry_run`	Yes
`plan_id`	Yes
`duration_s`	Yes
`executable`	Yes
`expires_at`	No	ISO-8601 UTC expiry of the plan handle
`violations`	No
`final_ee_pose`	Yes
`num_waypoints`	Yes
`force_monitoring`	Yes	Whether the backend currently provides an external wrench estimate. Without one the server cannot enforce the contact force limit, and execute_plan refuses to move unless the policy sets force.require_wrench: false
`velocity_scaling`	Yes
`requires_approval`	Yes
`tcp_path_length_m`	Yes
`acceleration_scaling`	Yes
`max_joint_travel_rad`	Yes
`final_joint_positions`	Yes
`start_joint_positions`	Yes
`max_joint_velocity_ratio`	Yes	Peak joint speed as a fraction of the joint limit
`max_joint_acceleration_ratio`	Yes	Peak joint acceleration (estimated from the waypoint timing) as a fraction of the joint limit

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 26, 2026

TDQS

A4.3/5.0

Behavior4/5

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

Annotations already declare readOnlyHint=true, and the description is consistent with that via '(do NOT move)'. It adds genuinely useful behavior beyond annotations: it uses inverse kinematics, the resulting path is joint-space interpolation so the TCP does not travel straight, and the plan is validated against the safety envelope. It stops short of describing failure modes such as unreachable goals or IK failure.

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?

Three tight sentences, front-loaded with the action and its most important constraint ('do NOT move'), then the path caveat, then the return. No filler or repetition of the name.

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

Completeness5/5

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

With an output schema covering the plan summary and annotations covering safety, the description supplies the remaining decision-critical context: path type, sibling routing, and safety validation. Nothing needed to invoke it correctly is missing.

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

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so every parameter (frame_id, position, orientation, velocity_scaling, acceleration_scaling) is already documented, including 'omit to keep current' for orientation. The description adds no further per-parameter semantics, so the baseline 3 applies.

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

Purpose5/5

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

Specific verb (Plan) plus specific resource and scope (motion bringing the TCP to a pose), and it explicitly marks the boundary 'do NOT move'. It also names the sibling it is not (plan_cartesian_path), so an agent can tell them apart without opening either schema.

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

Usage Guidelines4/5

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

It gives an explicit routing rule: use plan_cartesian_path when a straight-line TCP path is required, implying this tool is for redundant/IK-based goal-reaching plans. The '(do NOT move)' caveat steers the agent toward execute_plan for actual motion. It does not discuss plan_to_joints (joint-space goal vs Cartesian goal), leaving that comparison to inference.

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