MCP tools
passo.build MCP tools are exposed through Streamable HTTP. During rollout, some hosts use bearer auth as a transport bridge. The target product flow is local login from the agent host, with the session bound to user, tenant, and project. Deploy, SSO, Terraform, billing, and secret operations stay behind explicit human gates.
POST https://mcp.passo.build/mcp
tools/list is the source of truth. The catalog below is a stable subset; always
discover the live pyx_* and mesh_* families from the server rather than
hard-coding names.
Common errors
| Error | Meaning | User-safe next step |
|---|---|---|
401 | The agent is not authenticated or the token/session is invalid. | Start login or refresh the rollout token outside the repo. |
| Wrong project/session | The local repo does not match the active project. | Stop and select the correct project before writing evidence. |
| Missing tool | The docs mention a target flow that is not in the live catalog. | Use tools/list as truth; fall back to console if needed. |
| Stale fence or lease | Another agent owns newer task state. | Re-read the task/mesh state before writing. |
| Missing approval | The action is gated by deploy, cloud, SSO, billing, or secret policy. | Ask the human controller and attach evidence. |
Assessment & scope bridge
| Tool | Purpose |
|---|---|
pyx_assess_project_scope | Builds a product-scope report from answers, repository signals, and optional buildId projection. |
mesh_project_from_scope | Projects accepted scope gaps into mesh tasks for implementation agents. |
mesh_reflect_scope | Reflects live mesh state back onto a scope assessment (per-gap status/agent/evidence). |
mesh_board_snapshot | Returns current mesh task status and evidence links. |
mesh_context_get | Reads projected context documents such as build:<id>:context. |
Client-facing product tools
The target client-facing catalog is intentionally small. These tools may return
plain JSON, agentUi, or both:
| Tool | Purpose |
|---|---|
passobuild_project_prepare | Bind or resume project/session. |
passobuild_scope_assess | Convert repo signals and answers into accepted scope. |
passobuild_security_gate | Present SAST/dependency/secrets state and blockers. |
passobuild_implementation_plan | Convert scope gaps and SAST blockers into mesh tasks. |
passobuild_architecture_review | Review or generate PyxCloud topology after gates. |
passobuild_deploy_review | Compare providers and prepare deploy evidence. |
Low-level mesh tools remain available for actuators, debugging, and resumable work, but normal client flows should start from the product tools above.
Mesh coordination
The mesh exposes a pull/claim coordination surface — agents claim work; nobody assigns it. Core families:
- Presence —
mesh_agent_register,mesh_agent_heartbeat. - Pull loop —
mesh_task_next,mesh_task_claim,mesh_task_heartbeat,mesh_task_update,mesh_task_complete,mesh_task_release. - Authoring —
mesh_epic_create,mesh_task_create. - Global locks / interlock —
mesh_lock_acquire,mesh_lock_release,mesh_lock_list,mesh_approval_grant(admin). - KB / context —
mesh_kb_put,mesh_context_get,mesh_kb_search. - Board / events —
mesh_events_tail,mesh_board_snapshot.
For the working-memory tools (mesh_task_checkpoint, mesh_task_plan_set,
mesh_task_step_update, mesh_task_resume) see
Agent Mesh: working memory.