FaceLink
This server is FaceLink's MCP bridge to Blender: it lets AI/LLM clients inspect Blender scenes, plan and validate editable animation shots, stage changes for human review, apply or roll them back, and manage retargeting of armature actions.
Inspect Blender: list running FaceLink bridge instances, check health, scan scenes for entities, transforms, navigation meshes, armatures, bones, and Action inventories.
Validate shots: validate typed ShotSpecs (move_to, turn_to, look_at, wait, play_clip, camera) against a SceneSnapshot without changing Blender.
Preview shots: compile shots including navmesh paths and camera composition preflight, still without applying.
Stage for safe review: stage a scene patch in Blender for visible human approval, read the staged patch, apply it after review, or discard it.
Power-user bypass: apply a whitelisted scene patch directly without Blender review staging, and undo the most recent apply.
Retarget actions: validate, analyze, and suggest bone-mapping profiles for rename-only, baked-pose, or evaluated-pose retargeting.
History and recovery: list persistent revision history, roll back to a selected revision, and query the status of previously submitted Blender jobs.
Allows creation and editing of Blender scene animations through natural language instructions, with capabilities for scanning scenes, previewing shots, staging patches, and applying them as editable keyframes and transforms.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@FaceLinkCan you plan a shot where the character walks from the door to the table and looks at the camera, but stage it first?"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
FaceLink
FaceLink turns a constrained shot description into editable Blender scene animation. It is aimed at previs/white-model work: actors, props and cameras remain ordinary Blender objects with ordinary keyframes, so artists can drag, retime and override the result.
FaceLink is not a text-to-video generator and does not give an LLM unrestricted Python
execution. The model produces a typed ShotSpec; FaceLink validates it, compiles it into a
small whitelist of patch operations, stages a human-readable review in Blender, and changes
the scene only after the artist presses Apply Staged Patch.
Demo

This four-second demo is rendered from the included
editable .blend scene. The movement was applied through
FaceLink's real patch executor and remains 24 ordinary editable keyframe values—not a generated
video baked outside Blender.
Related MCP server: BlenderMCP
Current MVP
scans the open Blender scene and gives objects stable FaceLink IDs;
compiles
move_to,turn_to,look_at,waitandplay_clipbeats;creates/updates editable transforms, keyframes, cameras and tracking constraints;
plans transforms in world space and converts them for parented Blender objects;
exposes the workflow through an MCP server for Codex/ChatGPT-compatible MCP clients;
supports OpenAI API-key planning with Structured Outputs;
runs a localhost-only authenticated bridge between the MCP process and Blender;
supports Blender-side stage/review/apply/discard, persistent audit history and safe rollback to a selected current-session revision.
persists a bounded, payload-free task lifecycle journal for explicit startup recovery and never replays interrupted work automatically;
adds a bounded Blender task/recovery center for connection state, queue progress, queued-job cancellation, recent outcomes and privacy-safe startup guidance;
negotiates local bridge protocol 1.12/1.13 explicitly and attaches request/correlation IDs to jobs and stable errors for cross-layer troubleshooting;
exposes an authenticated, bounded diagnostic endpoint and a separate privacy-safe local JSON export without automatic upload;
rejects internally overlapping transform/action timelines, warns before overwriting existing keyframes and rejects colliding FaceLink NLA clips;
previews staged world-space motion paths and predicted camera frustums directly in the Blender viewport without creating scene datablocks;
scans explicitly marked navigation meshes and obstacles, plans deterministic multi-segment locomotion paths, and warns when an actor's swept bounds intersect a marked obstacle;
fingerprints the complete navigation environment so a newly added obstacle or edited navigation mesh invalidates an already staged plan;
inventories armature bone hierarchies and editable Blender Actions, including pose-bone channels, rest orientations, frame ranges and deterministic content fingerprints;
suggests review-only bone maps using deterministic name normalization, then measures mapped hierarchy, local rest axes and scale-normalized bone proportions before execution;
copies compatible Actions through an open
rename_onlybone-map profile, rewrites editable FCurve paths, places the result in NLA, and removes created copies during rollback;samples reviewed
bake_poseprofiles into ordinary editable target Actions, correcting different local rest axes and bone scale with explicit root-motion policy and bounded work;evaluates existing self-contained source-rig constraints and drivers with
bake_evaluated_pose, then bakes the final deform-bone pose into an ordinary editable Action;optionally transfers Armature object root motion as a placement-preserving relative delta, with source-unit or rig-scale-adjusted translation;
predicts the staged camera frame without creating scene datablocks, measuring target size, center offset, safe-area fit, clipping and center-point occlusion before the artist applies;
rejects a staged plan when a referenced transform, parent link, lock or scene timing value changed after the scene scan.
Blender 任务与恢复中心(开发分支)
打开 3D 视图 → 侧边栏 → FaceLink,点击 Start Bridge 后,顶部会显示当前连接、 队列、活动任务和最近结果。展开 Tasks 可以取消仍在排队的任务;运行中的任务不会被 异步强杀,只能在安全检查点协作式停止。由于 Blender 场景操作同步占用主线程,长任务 运行时面板按钮可能无法及时响应,运行中取消目前主要由独立 MCP/HTTP 客户端发起。 界面显示 Local bridge ready 只表示本机 Blender 桥接已就绪,不表示 AI、Codex 账号 或 API Key 已连接。
如果上一次 Blender 会话异常中断,面板会要求先检查场景、历史并重新扫描。点击
I Reviewed 只确认用户看过恢复提示,不会重放、应用、撤销或回滚任何任务。打开其他
.blend、未保存文件首次保存或 Save As 改变路径时,桥接会停止并要求为当前文件
重新启动,防止继续写入旧工作区日志。
恢复确认以前,Blender UI 会禁用应用暂存、撤销和历史回滚;本机 HTTP 还会拒绝上述
三类以及直接应用,返回 recovery_review_required 且不创建任务。扫描和读取等检查
操作仍可使用。
这一切片不包含 Blender 内的 Codex/ChatGPT 订阅登录或 API Key 表单,也不会读取
Codex 的 auth.json。完整状态、取消、恢复、文件切换和隐私边界见
Blender 任务与恢复中心。
Supported Blender versions
Primary: Blender 4.5 LTS (tested with 4.5.12)
Minimum: Blender 4.2 LTS
Best effort: Blender 5.x
The Blender 4.0.2 installation found on the development machine predates the extension baseline. FaceLink's source can still be loaded there for smoke testing, but 4.0 is not a declared supported version.
桥接协议、数据结构和升级/降级并不跟产品版本共用一个编号。当前未发布代码的桥接协议 为 1.13,只明确兼容 1.12 和 1.13;详见 兼容性与迁移政策。
Install the alpha release
Download FaceLink-Setup-0.3.9.exe from the
FaceLink 0.3.9 Alpha release,
open it, choose Check setup, then Install FaceLink.
This alpha EXE is not yet code-signed, so Windows SmartScreen may show an unknown-publisher
warning. Verify it against the release SHA256SUMS.txt before choosing More info → Run
anyway, and only use files downloaded from the official FaceLink release page.

FaceLink does not bundle Blender. It detects an existing official Blender 4.2-or-newer installation, which keeps the release small and lets each artist choose Blender 4.5 LTS or a newer compatible version. If Blender is missing, install it from the official Blender LTS page.
The graphical installer contains the FaceLink host, extension, checksum manifest and safe PowerShell backend in one small EXE. It verifies the embedded files, detects Python and Blender, installs both FaceLink components, and safely configures the shared local ChatGPT Desktop/Codex MCP file. It does not request administrator access or store an API key.
For a manual Windows install, keep the four raw release files together and run:
.\install-windows.ps1 `
-WheelPath .\facelink-0.3.9-py3-none-any.whl `
-ExtensionZipPath .\facelink-0.3.9.zip `
-ChecksumsPath .\SHA256SUMS.txtThe script verifies the release hashes, finds Python 3.11+ and Blender 4.2+, creates an
isolated FaceLink host, installs the extension and configures the exact facelink-mcp.exe path.
Pass -PlanOnly to inspect every resolved path without installing anything. Pass
-BlenderExe C:\path\to\blender.exe when Blender is portable or not on a conventional path.
Pass -SkipMcpConfiguration to leave the local MCP configuration untouched.
For an existing FaceLink extension, update it from Blender Preferences or remove the old
version before running the extension-install step.
After starting FaceLink's bridge in Blender, validate the complete setup:
facelink doctor --blender-exe C:\path\to\blender.exeDoctor 不打印 API Key 或 Blender 桥接 Bearer Token;缺少 API Key 只是警告,因为 MCP 客户端可以使用自己的模型。不过 Doctor 面向本机排错,仍可能显示 Blender、MCP 启动器 和发现目录的绝对路径,不应原样公开分享。需要生成支持附件时使用:
facelink diagnostics --out facelink-diagnostics.json该命令只在本地原子写出最多 1 MiB 的单个 JSON,默认不覆盖已有文件,也不会自动上传。 它通过严格允许列表排除绝对路径、场景/对象/骨骼/Action 名称、brief/prompt、请求 payload/result、原始异常、Token、API Key 和私钥;只保留版本、能力、计数、状态、稳定 错误码及随机关联编号。分享前仍应人工打开检查。隐私边界见 威胁模型。
To install the two components manually, continue below.
In Blender 4.2 or newer, open Edit → Preferences → Get Extensions → Install from Disk,
select facelink-0.3.9.zip, enable FaceLink, open the FaceLink tab in the 3D Viewport
sidebar and press Start Bridge.
Install the Python host in an isolated Python 3.11-or-newer environment:
py -3.11 -m venv .venv
.\.venv\Scripts\python -m pip install .\facelink-0.3.9-py3-none-any.whl
.\.venv\Scripts\facelink-mcpUse SHA256SUMS.txt from the release to verify every downloaded artifact. Continue below for
MCP client configuration and the safe stage/review/apply workflow.
Install for development
git clone https://github.com/xuebazhou-blip/FaceLink.git
cd FaceLink
$env:UV_CACHE_DIR = Join-Path $PWD '.cache\uv'
uv sync --extra dev
uv run pytestFor the reproducible multi-version acceptance matrix, including real extension installation:
./scripts/run_acceptance.ps1The harness writes JUnit, coverage, per-Blender JSON and command logs below artifacts/.
See docs/TESTING.md for the exact gates and known exclusions.
Build the Blender extension:
$env:FACELINK_BLENDER_EXE='C:\path\to\Blender\blender.exe' # optional if on PATH
./scripts/build_extension.ps1Then in Blender 4.5: Edit → Preferences → Get Extensions → Install from Disk, choose
dist/facelink-0.3.9.zip, enable FaceLink, and open the FaceLink tab in the 3D Viewport
sidebar. Press Start Bridge.
Run the MCP server:
uv run facelink-mcpSafely create or update the shared local ChatGPT Desktop/Codex configuration:
$projectRoot = (Resolve-Path .).Path
uv run facelink configure-mcp `
--mcp-launcher (Join-Path $projectRoot '.venv\Scripts\facelink-mcp.exe') `
--instance-dir (Join-Path $projectRoot '.facelink\instances')FaceLink backs up an existing ~/.codex/config.toml, preserves unrelated settings and owns
only its clearly marked block. The resulting OpenAI-compatible configuration is TOML:
[mcp_servers.facelink]
command = "C:\\path\\to\\FaceLink\\.venv\\Scripts\\facelink-mcp.exe"
enabled = true
[mcp_servers.facelink.env]
FACELINK_INSTANCE_DIR = "C:\\path\\to\\FaceLink\\.facelink\\instances"The ChatGPT desktop app, Codex CLI and Codex IDE extension share this local configuration.
ChatGPT on the web does not read local MCP configuration and would require a separately hosted
plugin. See the official OpenAI MCP documentation.
The same FACELINK_INSTANCE_DIR is set for future Blender processes; restart Blender and the
MCP client after installation.
With an MCP client, the safe default sequence is:
scan_sceneturn the user's natural-language request into a typed shot and call
preview_shotcall
stage_scene_patchlet the user inspect the summary in Blender and press Apply Staged Patch or Discard
This path uses the model already available in the MCP client; FaceLink itself needs no API
key. apply_scene_patch remains available as an explicit power-user bypass.
BYOK planning
$env:OPENAI_API_KEY='your-key'
uv run facelink plan --brief "Cube walks to Marker in 2 seconds, camera follows Cube" `
--snapshot scene.json --out shot.jsonOr scan the running Blender scene, plan, compile and stage the result in one command:
$env:OPENAI_API_KEY='your-key'
uv run facelink workflow `
--brief "Cube walks to Marker in 2 seconds, camera follows Cube"The command does not apply anything. Review and approve the staged result in Blender.
To make an existing Action target a compatible armature whose bone names differ, pass a reviewed open profile:
uv run facelink validate-profile `
--profile profiles/mixamo_to_facelink_compact.json
uv run facelink suggest-profile `
--snapshot scene.json --source-rig source-armature-id `
--target-rig target-armature-id --action "Mixamo Walk" `
--name "Reviewed map" --out suggestion.json
uv run facelink analyze-profile `
--profile profiles/mixamo_to_facelink_compact.json `
--snapshot scene.json --source-rig source-armature-id `
--target-rig target-armature-id --out compatibility.json
uv run facelink plan `
--brief "Apply Mixamo Walk to the target rig for two seconds" `
--snapshot scene.json `
--retarget-profile profiles/mixamo_to_facelink_compact.json `
--out shot.jsonSuggestions are never applied automatically and always carry review_required: true. The
compatibility result is safe, review, bake_required or incompatible. The compiler
blocks rename_only when hierarchy, rest orientation or proportions require baking. FaceLink
fingerprints both Actions and referenced rigs, so curve or rest-pose edits after scanning fail
before mutation; it also blocks unscaled pose-bone translation channels across differently
sized rigs. Generated Actions and NLA strips remain ordinary editable Blender data. See
profiles/README.md and
examples/retargeted_clip_shot.json.
When analysis says bake_required because local rest axes or rig scale differ, change the
reviewed profile to adapter: "bake_pose", set its explicit source_rig, and optionally set
sample_step (1-16) and root_motion (scale, preserve or drop). FaceLink samples the
source Action's native frame range, writes linear location/rotation/scale keys to a normal
target Action, and puts it in the same editable NLA workflow. Object-level Action channels are
omitted unless object_motion is explicit; otherwise root motion must be on a mapped root pose
bone. This first adapter requires equivalent
mapped parent hierarchy and unconstrained source/target deform bones. See
profiles/mixamo_to_facelink_compact_bake.json
and examples/baked_retargeted_clip_shot.json.
When the source Action animates controller bones or custom properties and the source deform
bones receive their final motion through constraints/drivers, use
adapter: "bake_evaluated_pose". The reviewed bone_map maps source deform bones—not the
controller channels—to target deform bones. Version 1 permits only dependencies on the same
source armature object/data, rejects external helper objects and scene-driven variables, and
still requires equivalent mapped parent hierarchy plus unconstrained/undriven target bones.
It does not discover controllers or convert IK/FK systems automatically. See
profiles/controller_to_deform_evaluated_bake.json
and examples/evaluated_retargeted_clip_shot.json.
If overall character movement lives on the source Armature object, add
object_motion: "preserve" or "scale" to either bake adapter. FaceLink uses the source
object's transform relative to its first sampled frame, applies that delta after the target's
current world transform, and writes ordinary object location/rotation/scale FCurves into the
same generated Action. scale multiplies delta translation by the mapped-rig median length
ratio; preserve keeps source units. Version 1 requires unparented source/target Armatures with
no object constraints or driven target object transforms. See
profiles/object_motion_bake.json and
examples/object_motion_clip_shot.json.
Inspect or roll back FaceLink revisions from the command line:
uv run facelink history
uv run facelink rollback --revision rev-0123456789abcdefRevision metadata is stored in the .blend file. Executable rollback snapshots intentionally
remain session-only because they contain live Blender datablock references. Rolling back an
older revision also rolls back every newer FaceLink revision to preserve a linear scene state.
An API key is optional when an MCP client performs the language-model planning itself. ChatGPT subscriptions and OpenAI API billing are separate; a ChatGPT membership is not an API key. See docs/ARCHITECTURE.md for the trust boundary.
使用 BYOK 规划时,FaceLink 会把用户 brief、序列化 Scene Snapshot 和可选重定向配置发给
所配置的 OpenAI 兼容端点;这些内容可能包含场景、对象、骨骼、Action 名称和变换。
API Key 不会进入 .blend、任务日志或安全诊断包,但远端提供商、代理及自定义
base_url 的数据政策仍由用户负责审查。MCP 客户端也可能按自身政策把工具输入/输出
发送给其模型提供商。
Navigation workflow
Select a walkable mesh and use FaceLink → Navigation → Navmesh. Select walls, props or
other blocking objects and mark them as Obstacle. A move_to beat keeps the legacy
straight line by default; set path_mode to navmesh to route through connected navigation
triangles. The compiler distributes ordinary editable location keyframes by path distance
and forces linear interpolation so curved handles cannot leave the walkable corridor.
Navigation is deliberately explicit. FaceLink does not guess from object names or silently treat every mesh as an obstacle. Current v0.3.0 planning is projected onto XY and is intended for single-level previs floors; stacked floors, live moving obstacles and crowd routing are not yet supported. See examples/navmesh_walk_shot.json.
Camera composition preflight
Camera shots with a target are checked during staging. FaceLink projects the target's
world-space bounds into the predicted camera frame and reports clipping, unsafe margins,
subject size and center offset. A read-only Blender ray cast reports when another object blocks
the target center. dolly_in checks both its start and end positions. Thresholds are typed in
camera.composition, remain visible in the ShotSpec and can be disabled explicitly. See
examples/composition_checked_shot.json.
This is a deterministic preflight, not an artistic quality score. It does not render, use a vision model, judge lighting or guarantee that every part of a complex subject is unoccluded. Version 0.3.3 evaluates perspective cameras without lens shift and reports other projection types as unsupported instead of returning misleading metrics.
Repository map
src/facelink/ Core schemas, compiler, bridge client, providers, CLI and MCP server
blender_extension/ Zero-dependency Blender extension and local bridge
schemas/ Portable JSON Schema for integrations
examples/ Example editable shot specifications
tests/ Unit tests and a Blender headless smoke test
scripts/ Build and verification scripts
docs/ Architecture, protocol and development notesProject status
Version 0.3.9 is a creator-review alpha, not yet a production animation system. It performs bounded transform-aware pose baking for reviewed mappings and can evaluate existing constraints and drivers when every dependency stays on the explicit source armature. It can also transfer unparented, unconstrained Armature-object motion without moving the target's starting placement. It does not infer controllers, translate IK/FK systems, follow external helper objects, solve different mapped parent hierarchies, handle parented/constrained object roots, synthesize missing motion or judge the visual result. Multi-level navigation, multi-shot sequencing and visual diff overlays remain follow-up work.
The Windows release now has a single-file graphical installer, safe local MCP configuration, a secret-safe environment doctor and a reproducible real-Blender demo. Before promoting this alpha more broadly, test installation with non-developer users and complete Linux/macOS installation coverage.
License
FaceLink is free software licensed under GNU GPL version 3 or any later version. The Blender extension distribution includes the same license text.
Available Tools
17 toolsanalyze_retarget_profileC
Measure hierarchy, rest-axis and proportion safety for a reviewed bone map.
| Name | Required | Description | Default |
|---|---|---|---|
| profile | Yes | ||
| source_rig_id | Yes | ||
| target_rig_id | Yes | ||
| scene_snapshot | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must disclose behavior, but it only says 'Measure', which implies a read-only operation without confirming side effects or lack of mutations. It fails to mention return format, potential errors, or any safety guarantees.
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 a single sentence, which is brief but severely under-specified. It omits critical information like parameter roles, expected inputs, and output semantics, making it more under-specified than concise.
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?
Given the high complexity of the input schemas (nested object types, many fields) and the existence of an output schema, the description lacks completeness. It doesn't explain what 'measure safety' means in terms of return values or how the tool evaluates the bone map against the provided rigs and scene.
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?
The schema contains 4 complex parameters (profile, source_rig_id, target_rig_id, scene_snapshot) with 0% description coverage. The description provides no explanation of what these parameters mean or how they are used, leaving the agent without essential semantic guidance.
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?
The description uses the verb 'Measure' and specifies three measurable aspects (hierarchy, rest-axis, proportion safety) for a reviewed bone map. This distinguishes it from sibling tools like validate_retarget_profile, though the phrase 'reviewed bone map' is somewhat unclear and doesn't explicitly reference the profile object.
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?
No guidance is provided on when to use this tool versus alternatives such as validate_retarget_profile or suggest_retarget_profile_map. The description gives no context for selection or preconditions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
apply_scene_patchB
Power-user escape hatch: apply a white-listed patch without Blender review staging.
| Name | Required | Description | Default |
|---|---|---|---|
| patch | Yes | ||
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must disclose behavioral traits itself. It indicates a bypass of review staging but lacks details on side effects, validation, undo capability, or safety implications. This is insufficient for a mutation tool that applies patches directly.
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 one clear, front-loaded sentence that efficiently expresses the core purpose. It is not bloated, though it could be expanded slightly without losing conciseness.
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?
Given the tool's complexity (large nested schema), absence of annotations, and no parameter descriptions, a single sentence is inadequate. Major gaps include patch structure, fingerprint validation, the meaning of 'white-listed', and workflow integration with sibling tools.
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% and the description provides zero information about the patch parameter or instance_id. The complex ScenePatch schema is left entirely self-documenting, leaving the agent without semantic guidance for constructing valid inputs.
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?
The description clearly states the action ('apply'), the resource ('a white-listed patch'), and the key differentiator ('without Blender review staging'), effectively distinguishing it from the staged patch workflow represented by sibling tools.
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?
The phrase 'power-user escape hatch' implies an alternative to the normal staging workflow, but it does not explicitly name alternatives (like stage_scene_patch) or provide when-not-to-use guidance. The usage context is implied rather than clearly stated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
apply_staged_patchC
Apply the patch that a human has reviewed in Blender.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It only states that a human-reviewed patch is applied, but doesn't disclose side effects, reversibility, or whether it requires any prerequisites. For a mutating operation, this is insufficient behavioral transparency.
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?
Single sentence with no filler, front-loads the core action. It's appropriately sized for a simple tool, though it sacrifices completeness for brevity.
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?
The tool has an output schema and low parameter count, but the description omits crucial context about the patch application workflow, such as whether it can be undone, how it relates to staged patches, or what the output means. Given the sibling tools suggest a review/apply pipeline, more context would be needed.
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?
The schema lists one optional parameter, instance_id, with no description in the schema (0% coverage). The description provides no context for what instance_id means or how it should be used, leaving the agent to guess. Since the parameter name is relatively self-explanatory, it's not a 0, but the description adds no value.
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?
The description uses the verb 'Apply' and identifies the resource as 'the patch that a human has reviewed in Blender,' clearly distinguishing it from staging or discarding operations. However, it doesn't explicitly contrast with apply_scene_patch, a closely named sibling, so it's clear but not fully differentiated.
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?
The phrase 'that a human has reviewed' implies the appropriate time is after human review, offering some guidance. But there are no explicit when-to-use versus alternatives, no mention of workflow steps like get_staged_patch or discard_staged_patch, and no exclusions. The guidance is implied rather than explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
discard_staged_patchA
Discard the staged patch without changing Blender.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the transparency burden. It reveals a key behavioral aspect—this operation does not change Blender—but does not disclose other important details such as idempotency, whether the discard is reversible, or any side effects on the patch data. More specifics would be needed for full transparency.
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 a single, single-purpose sentence without extraneous words. It effectively communicates the tool's function in as few words as possible, demonstrating excellent conciseness and structure.
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 simple tool with an optional parameter and an existing output schema, the description adequately covers the core functionality. It could be improved by noting the consequence of discarding (e.g., the patch is permanently lost), but overall it is sufficient for an agent to understand the primary use.
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?
The lone parameter instance_id has no description in the schema, and the description does not mention it at all. With 0% schema description coverage, the tool description should compensate but does not, leaving the agent to rely on the parameter name alone.
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?
The description uses a specific verb 'discard' and names the resource 'staged patch,' clearly identifying what the tool does. The phrase 'without changing Blender' adds a distinguishing context, differentiating it from sibling tools like apply_staged_patch or undo_last_apply.
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?
The description implies the tool is for discarding a staged patch, but it does not explicitly state when to use it versus alternatives like apply_staged_patch or get_staged_patch. No exclusions or alternative guidance is provided, so usage context is only implicitly conveyed.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
facelink_healthB
Check connectivity and capabilities for one FaceLink Blender instance.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description alone must convey behavioral traits such as read-only safety, side effects, or behavior when instance_id is null, but none of this is stated. 'Check' weakly implies a read operation, but the description does not disclose what happens to the connection, what capabilities are probed, or any error behavior.
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 a single, front-loaded sentence of nine words with no filler or redundancy. It communicates the core purpose immediately, which is appropriate for a simple health-check tool.
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?
The tool has low complexity and an output schema, so return-value details are not required, but the description still lacks usage guidance and behavioral context. It is minimally viable for selecting the tool, but an agent would have to infer when to call it and what optional-instance_id omission implies.
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 needed to explain instance_id, but it only says 'one FaceLink Blender instance.' It does not clarify that the parameter is optional, what null/default means, or how the instance_id is used. The schema provides type/default, but the description adds little semantic value.
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?
The description uses a specific verb ('Check') and names the resource ('connectivity and capabilities for one FaceLink Blender instance'), making the tool's scope clear. This also distinguishes it from sibling tools like list_blender_instances or get_blender_job, which cover different facets.
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?
The wording implies this is a health/capability check for one specific instance, but it provides no explicit guidance on when to use it, no prerequisites (e.g., obtaining instance_id via list_blender_instances), and no exclusions versus sibling tools. The context is only implicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_blender_jobA
Get the status of a previously submitted Blender job.
| Name | Required | Description | Default |
|---|---|---|---|
| job_id | Yes | ||
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must carry the burden of behavioral disclosure. It accurately indicates this is a read-only operation, but it doesn't explain what happens when the job ID is invalid, whether it returns partial results, or any side effects. The simplicity of the tool lowers the risk, but the description adds no extra context beyond the basic read semantics.
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?
A single, concise sentence that gets straight to the point. It contains no fluff, no redundant content, and is immediately scannable. The length is appropriate for the tool's simplicity.
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?
The presence of an output schema means return-value documentation is already handled, so the description does not need to explain response fields. For a simple get-status operation, the description covers the core scenario. It doesn't mention error cases or status semantics, but given the tool's narrow scope and the output schema, it is sufficiently complete.
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 needed to compensate. The word 'Blender job' implies that 'job_id' refers to the Blender job identifier, but 'instance_id' is left entirely unexplained. The optional parameter's purpose is unclear—does it specify a particular instance or filter? Because the description does not clarify either parameter beyond what the schema already shows, it falls short for a 0%-coverage case.
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?
The description uses a specific verb and object: 'Get the status of a previously submitted Blender job.' It clearly identifies the resource (Blender job) and the action (retrieve status), and it implicitly distinguishes this from siblings like 'list_blender_instances' or 'preview_shot.' The phrase 'previously submitted' hints that the job must already exist, which adds 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?
The description gives no explicit guidance on when to use this tool versus alternatives, nor does it mention any prerequisites or exclusions. Usage is only implied by the verb 'get' and the term 'status.' No comparison with sibling tools is provided, so this is a bare minimum.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_staged_patchA
Read the patch and artist-facing summary currently waiting for approval.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations are not provided, so the description carries the burden. It says 'Read', which indicates a non-mutating operation, but it doesn't disclose details such as whether the patch is returned in a specific format, what happens if there's no staged patch, or any rate limits. It adds minimal behavioral context beyond the verb itself.
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 a single concise sentence, about 12 words, with no redundancy. It is front-loaded with the verb 'Read' and quickly identifies the target. Perfectly concise.
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 an output schema present, the description needn't explain return values, but it still lacks context on preconditions (e.g., a staged patch exists), side effects, or the meaning of instance_id. Given the sibling tools like apply_staged_patch and discard_staged_patch, it is clearly part of a workflow, but the description doesn't elaborate. Overall, adequate but with notable gaps, earning a 3.
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%, but there is only one parameter (instance_id) that is optional and nullable. The description doesn't explain what instance_id refers to (likely the instance identifier) or how it affects the result. Given the low coverage, the description should compensate, but it adds no param information. The baseline for low coverage is below 3, but the single param is simple, so a 3 seems appropriate.
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?
The description clearly states the tool reads (Read) a patch and artist-facing summary waiting for approval, distinguishing it from apply_staged_patch and discard_staged_patch. It is specific about the resource (staged patch) and its state (waiting for approval), though it doesn't explicitly mention the return type.
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?
The phrase 'currently waiting for approval' implies it's used before applying or discarding a staged patch, which provides context. However, it doesn't explicitly state when not to use it or mention alternatives like get_blender_job, so it falls short of a 5.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_blender_instancesA
List Blender windows that currently have the FaceLink bridge running.
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries full burden. It adds the behavioral condition 'currently have the FaceLink bridge running', which is useful. However, it does not explicitly state read-only nature or side effects; while 'List' implies a safe operation, the description could be more explicit about being read-only and non-destructive.
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 a single sentence, front-loaded with the verb, and contains no filler. Every word contributes meaning, making it highly concise and easy to parse.
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?
Given the simplicity of the tool (no params, no annotations, and an output schema exists), the description is complete. It states what it lists and the specific filter condition. The output schema covers return values, so no further detail is needed.
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?
The tool has zero parameters and the schema is empty, so there is nothing to explain. The baseline for 0 params is 4, and the description does not need to add parameter details. It appropriately avoids irrelevant information.
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?
The description clearly states the action ('List') and the resource ('Blender windows that currently have the FaceLink bridge running'). It distinguishes from sibling tools like facelink_health and get_blender_job by specifying the exact scope (only instances with the bridge active).
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?
The description implies usage when you need to enumerate active Blender instances. It does not explicitly mention alternatives or exclusions, but the context is clear given the sibling list; the agent can infer this is the tool for listing connected instances. No explicit guidance on when not to use, but the purpose is unambiguous.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
list_revision_historyA
List persistent FaceLink audit entries and current-session rollback availability.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It discloses that audit entries are persistent and rollback availability is current-session, which adds context. However, it doesn't mention side effects, read-only nature, or what 'availability' entails beyond the schema.
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 one concise sentence, front-loaded with the core action. It is efficient, though it could benefit from a brief note on the parameter.
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?
Given an output schema exists, the description need not explain return values. But with no annotations and a single undocumented parameter, it leaves some gaps about why instance_id matters and what 'rollback availability' means practically. It's adequate but not complete.
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 0%, and there is only one parameter with no description. The description does not explain what instance_id does, so it fails to add meaning. However, with only one optional parameter, the gap is less critical, but the description should at least hint at filtering by instance.
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?
The description clearly states the tool lists persistent audit entries and rollback availability for FaceLink, using specific verbs and resources. It distinguishes from siblings like rollback_to_revision by focusing on listing, though it doesn't explicitly name 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?
It implies usage for auditing and checking rollback, but no explicit when-to-use or when-not-to-use guidance. Sibling tools suggest a broader ecosystem, but the description lacks exclusions or alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
preview_shotB
Compile a shot, including deterministic navmesh paths, without applying it.
| Name | Required | Description | Default |
|---|---|---|---|
| shot_spec | Yes | ||
| scene_snapshot | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the burden of behavioral disclosure. It usefully states that the tool does not apply the shot and that navmesh paths are deterministic, but it does not clarify whether temporary state is created, what the compiled output represents, or whether a valid scene snapshot is a prerequisite.
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 a single sentence that front-loads the verb and key constraints, with no filler, repetition, or vague qualifiers. It conveys the core purpose and the most important behavioral qualifier extremely efficiently.
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?
Despite a very complex schema with two large required structs and no annotations, the description is only one sentence. The output schema exists, so return values need not be detailed, but the description omits invocation context, prerequisites, and the distinction from validation/staging tools, making it insufficient for reliable tool selection in a complex workflow.
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%, yet the description adds no meaning to the two required top-level parameters, shot_spec and scene_snapshot, or how they interact. The parameter names are somewhat self-explanatory, but the description fails to compensate for the absent schema descriptions.
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?
The description uses a specific verb ('Compile') and resource ('shot'), and adds scope via 'including deterministic navmesh paths' and 'without applying it,' which distinguishes it from apply/stage tools. It is clear enough for a preview action, though 'compile' is somewhat domain-specific and does not explicitly contrast with validate_shot_spec.
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?
The phrase 'without applying it' implies this is for previewing before an apply/stage action, giving some usage context. However, it never names alternatives like apply_scene_patch, stage_scene_patch, or validate_shot_spec, nor states when to prefer this tool over them.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
rollback_to_revisionB
Undo the selected revision and every newer FaceLink revision in this session.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No | ||
| revision_id | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It discloses the scope of the operation ('selected revision and every newer') and session-level scoping, which is useful. However, it does not state whether the operation is reversible, whether it creates a new revision, or how it affects instances, leaving important safety aspects undisclosed.
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 a single, front-loaded sentence with no superfluous words. It conveys the core action and scope in 12 words, achieving excellent conciseness without sacrificing immediate clarity.
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 rollback operation with no annotations, the description omits critical context: the role of instance_id, the permanence of the undo, and any relationship to the output schema. While the output schema is available, the description is not complete enough for safe and correct invocation.
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% and the description does not map 'selected revision' to the revision_id parameter or explain the purpose of instance_id. The agent cannot derive parameter meanings from the description beyond their names, and instance_id is entirely unexplained.
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?
The description uses the specific verb 'Undo' with the resource 'FaceLink revision' and explicitly defines the scope as 'the selected revision and every newer', which clearly distinguishes it from sibling tools like list_revision_history and undo_last_apply. The purpose is immediately understandable.
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?
No explicit guidance is given on when to use this tool versus alternatives. It does not mention list_revision_history, undo_last_apply, or any criteria for when a rollback is appropriate, leaving the agent to infer usage from the broad description.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
scan_sceneB
Read stable IDs, bounds, nav data, armature bones and Action channel inventories.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
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. While 'Read' implies a read-only operation, it does not explicitly state safety, authorization requirements, or potential side effects, leaving the agent uncertain about the tool's impact.
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 a single, focused sentence that lists the data types without any redundant wording or unnecessary detail. It front-loads the action and immediately conveys the scope of the tool.
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?
Despite having an output schema (so return format disclosure is less critical), the description remains incomplete. It misses usage context, parameter semantics, and any indication of when this tool is appropriate, leaving an agent underprepared to invoke it correctly.
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?
The sole parameter instance_id is completely absent from the description, and the schema has no description for it (0% coverage). The description fails to explain what this parameter is for or how it affects the scan, forcing the agent to infer its meaning from the title alone.
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?
The description uses the verb 'Read' and explicitly lists the data types (stable IDs, bounds, nav data, armature bones, Action channel inventories), making the tool's purpose specific and understandable. It clearly distinguishes from siblings by focusing on a broad scene scan rather than specialized validation or analysis, even though it doesn't name 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?
The description provides no guidance on when to use this tool versus alternatives. It lacks any mention of use cases, prerequisites, or contexts where this scan is preferred, and doesn't address when not to use it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
stage_scene_patchA
Stage a patch in Blender for visible human review without changing the scene.
| Name | Required | Description | Default |
|---|---|---|---|
| patch | Yes | ||
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description is transparent about the key behavior: it stages the patch without modifying the scene. However, it does not detail potential side effects (e.g., storing the patch, requiring permissions) or what happens to existing staged patches. Given the lack of annotations, it covers the most critical behavior but not exhaustively.
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 a single, clear sentence with no fluff. It efficiently conveys purpose and behavior without unnecessary detail.
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?
The description is sufficient for a basic understanding of the operation, but it omits any context about the patch structure, the meaning of 'staging', or how it relates to other tools like get_staged_patch or discard_staged_patch. While an output schema exists (so return values are not required), the description does not address prerequisites or error conditions.
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 0%. The description does not explain any of the parameters (patch, instance_id) or the nested structure (ScenePatch, PatchOperation). With a complex schema, this omission leaves the agent without guidance on how to construct valid inputs, failing to compensate for the low schema coverage.
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?
The description clearly states the tool's purpose: to stage a patch in Blender for human review, explicitly noting it does not change the scene. This distinguishes it from apply_scene_patch and other sibling tools.
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?
It specifies when to use it (for review before applying) and highlights the non-destructive nature ('without changing the scene'), giving clear guidance. It does not explicitly mention when not to use it, but the context implies it is for staging rather than applying.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
suggest_retarget_profile_mapB
Suggest exact/normalized/alias bone matches; output always requires human review.
| Name | Required | Description | Default |
|---|---|---|---|
| action_name | No | ||
| profile_name | Yes | ||
| source_rig_id | Yes | ||
| target_rig_id | Yes | ||
| scene_snapshot | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It discloses an important behavioral trait: 'output always requires human review', which implies the tool doesn't commit changes and returns suggestions only. However, it does not describe what happens on failure, whether the output is a full map or just candidate matches, or what the output schema contains (though an output schema exists). The description adds the human-review requirement, which is valuable, but it's minimal.
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 extremely concise: one sentence with two clauses. It front-loads the core purpose and adds one behavioral note. No waste, but it is so short it lacks detail for other dimensions. For what it intends to cover, it's 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?
The tool takes a complex scene_snapshot object, has an output schema, and is in a domain where sibling tools suggest a workflow (validate/analyze/suggest). The description is insufficient: it does not mention how the scene_snapshot is used, whether action_name is required for generating a map, what the output format is (despite an output schema), or potential side effects. Given the complexity of the input and the tool's role in a pipeline, the description is too thin.
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%, meaning the description provides no parameter explanations beyond what the schema names suggest. The schema itself has 5 parameters (source_rig_id, target_rig_id, profile_name, scene_snapshot, action_name optional) with clear names and types, but no descriptions anywhere. The tool description does not explain the role of scene_snapshot or action_name, nor how they affect the suggestion. Since coverage is 0%, the description must compensate, and it fails to do so.
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?
The description clearly states the tool's purpose: 'Suggest exact/normalized/alias bone matches' for retarget profiles. It identifies the specific action (suggest bone matches) and the resource (retarget profile map). However, it doesn't explicitly distinguish itself from sibling tools like 'validate_retarget_profile' or 'analyze_retarget_profile', though the verb 'suggest' implies a generative step versus validation/analysis.
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?
The description implies it's used when you need to suggest bone matches for a retarget profile, but it doesn't explicitly state when to use it versus alternatives like 'validate_retarget_profile' or 'analyze_retarget_profile'. It also doesn't mention prerequisites (e.g., that the profile must exist) or that the scene_snapshot is required. The sentence 'output always requires human review' gives some usage guidance (the output shouldn't be applied automatically), but it lacks explicit exclusions or alternative tool recommendations.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
undo_last_applyC
Ask Blender to undo the most recent edit.
| Name | Required | Description | Default |
|---|---|---|---|
| instance_id | No |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It only says 'undo,' but fails to mention side effects (e.g., whether it is destructive, if there's an undo history limit, or what happens if there are no edits to undo). The optional instance_id parameter's role is also unexplored.
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 a single, concise sentence with no fluff. It is appropriately front-loaded, though its brevity sacrifices important detail.
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?
Given the presence of an output schema and only one optional parameter, a slightly richer description would suffice. However, the description omits crucial context about undo scope, error behavior, and when to use this tool, making it incomplete for a mutating operation.
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?
The input schema has one parameter, instance_id, but the description provides zero explanation of what it does or how it affects the undo operation. With 0% schema description coverage, the description must compensate but doesn't.
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?
The description clearly states the action ('undo') and the target ('most recent edit') in Blender. However, it does not distinguish from sibling tools like rollback_to_revision, which also reverts changes, so it misses the chance to differentiate.
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?
No guidance is given on when to use this tool versus alternatives like rollback_to_revision or other undo mechanisms. The description only states what it does, not when it is appropriate.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
validate_retarget_profileA
Validate a rename-only or sampled pose-bake profile without changing Blender.
| Name | Required | Description | Default |
|---|---|---|---|
| profile | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
There are no annotations, so the description carries the burden. It explicitly states 'without changing Blender' which discloses non-destructive behavior. However, it doesn't disclose what the validation actually checks (e.g., bone map validity, adapter constraints) or what the output looks like, though an output schema exists.
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 a single, concise sentence that efficiently conveys the purpose and key constraint. No wasted words, and the key phrase 'without changing Blender' is front-loaded.
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?
The tool has an output schema (though not shown in the context) and a single complex parameter. The description is minimal but adequate for a validation tool with a clear non-destructive guarantee. It could benefit from noting what validation entails, but given the schema richness the description is reasonably complete.
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?
The tool has only one parameter, 'profile', which is fully defined in the input schema with a detailed retarget profile structure. Schema description coverage is 0%, but the schema itself provides rich semantics for the profile. The description adds minimal value beyond stating the validation scope, so a baseline of 4 is appropriate given the strong schema.
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?
The description clearly states the tool validates a retarget profile (rename-only or sampled pose-bake) and explicitly notes it does not change Blender. This distinguishes it from other profile-related tools like analyze_retarget_profile and suggest_retarget_profile_map.
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?
The description implies usage for validating a profile before applying, and the explicit 'without changing Blender' provides a key safety context. However, it does not specify when to use this over analyze_retarget_profile or other validation tools, nor does it mention any prerequisites or alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
validate_shot_specC
Validate a typed shot without changing Blender.
| Name | Required | Description | Default |
|---|---|---|---|
| shot_spec | Yes | ||
| scene_snapshot | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
No output parameters | ||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description discloses a key behavioral trait (non-destructive, 'without changing Blender'), which is valuable given no annotations are provided. However, it omits other important behaviors like return values, error handling, or side effects, leaving the agent to infer from the output schema.
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 a single sentence with no wasted words, front-loading the action verb. It is efficient, though perhaps too terse given the tool's complexity, but conciseness itself is good.
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 tool with two highly complex nested parameters and an output schema, the description is severely inadequate. It provides zero context about validation logic, constraints, or expected behavior, making it almost useless for an agent to gauge what will happen or how to interpret results.
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%, and the description provides no information about the two parameters (shot_spec and scene_snapshot). While 'typed shot' hints at shot_spec, scene_snapshot is completely unmentioned, failing to compensate for the low schema coverage.
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?
The description clearly states the tool validates a typed shot and explicitly notes it does not change Blender. It distinguishes from siblings like preview_shot by emphasizing validation over previewing, though it does not elaborate on what validation entails.
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?
No guidance is provided on when to use this tool versus alternatives. The only hint is 'without changing Blender,' implying a dry-run safety check, but there is no explicit mention of use cases, exclusions, or related tools such as preview_shot or apply_scene_patch.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
17 tool updates
v0.3.8- First observed
analyze_retarget_profile - First observed
apply_scene_patch - First observed
apply_staged_patch - First observed
discard_staged_patch - First observed
facelink_health - First observed
get_blender_job - First observed
get_staged_patch - First observed
list_blender_instances - First observed
list_revision_history - First observed
preview_shot - First observed
rollback_to_revision - First observed
scan_scene - First observed
stage_scene_patch - First observed
suggest_retarget_profile_map - First observed
undo_last_apply - First observed
validate_retarget_profile - First observed
validate_shot_spec
TDQS
Scored across 17 tools
The tools are largely separated by lifecycle stage and resource type, such as validate, preview, stage, apply, and rollback. A couple of pairs, like validate_retarget_profile vs analyze_retarget_profile and apply_staged_patch vs apply_scene_patch, are close enough to require careful reading, but the descriptions do distinguish them.
Most tools follow a clean action_object snake_case pattern like list_, get_, validate_, stage_, apply_, and discard_. facelink_health breaks the pattern as a noun phrase, and rollback_to_revision uses a preposition instead of a direct object, but these are minor deviations.
17 tools is slightly above the typical 3-15 range, but the server covers several distinct workflow areas: instance health, retargeting, shots, staged patches, and revisions. The count is reasonable for the scope, though it could be tightened.
The set covers the core safety-oriented lifecycle: scan, validate, preview, stage, review, apply, and rollback. Obvious minor gaps exist, such as no Blender job submission/cancellation and no explicit apply/save for retarget profiles, but agents can work around them via scene patches and external job submission.
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