add_ik_retarget_chain

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

Annotations already cover the safety profile (non-destructive, non-idempotent, not open-world), and the description adds real behavioral detail: the chain name is engine-uniquified so chain_name must be read back, and a failed save yields success=false with saved=false and save_error. That is meaningful context an agent cannot derive from the annotations alone.

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 action and constraint, then a compact return-shape block. Most sentences earn their place; the returns block is justified because no output schema exists. Slightly verbose but well-structured.

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?

With no output schema, the description appropriately documents the return fields and error semantics, and covers the uniqueness/save behavior. Combined with annotations and a fully documented schema, an agent has enough to call it correctly; only explicit alternative-tool guidance is missing.

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 each parameter is already documented in the schema. The description restates the start_bone/end_bone skeleton constraint and notes the goal is optional, adding little beyond the schema, so the baseline of 3 applies.

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 (Add) and resource (retarget bone chain from start_bone to end_bone) targeting an IK Rig asset, which distinguishes it clearly from siblings like add_ik_goal, add_ik_solver, and set_ik_retarget_chain_bones. The optional IK goal tie-in further narrows the scope.

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?

Gives a clear precondition (both bones must exist in the rig skeleton) and states the tool saves the asset, which tells the agent this is a mutating creation step. It does not explicitly contrast against alternatives like rename_ik_retarget_chain or set_ik_retarget_chain_bones, so it stops short of full when/when-not routing.

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