add_obstacleAdd a solid block obstacle to the FDS fire model by specifying its bounding box coordinates in metres, defining geometry for simulation.
Add an obstacle (solid block) to the FDS model. XB=[x1,x2,y1,y2,z1,z2] in metres. [bulc-mcp rules] GEN-003 — bulc_knowledge_search ""
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Unique identifier | |
| xb | Yes | Bounding box [x1,x2,y1,y2,z1,z2] | |
| surf_ids | No | Surface IDs for faces |
Changes observed during successful MCP inspections.
v4.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so mutability and non-idempotence are covered. The description adds the coordinate ordering and metre units, plus a governance-rule pointer, but says nothing about duplicate-id behavior, overlap handling, mesh requirements, or what surf_ids do.
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?
Two short sentences, front-loaded with the action and immediately followed by the coordinate contract. The trailing rule reference is terse rather than bloated, though its unexplained angle-bracket syntax costs a bit of 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 geometry-creating mutation tool with no output schema, the essentials (verb, target model, coordinate format and units) are present, and annotations carry the safety profile. It still omits surf_ids semantics, uniqueness constraints, and any hint about prerequisites such as an existing mesh.
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 100%, so the schema already documents id, xb and surf_ids, and the baseline is 3. The description's only added meaning is the unit ('in metres') and the axis ordering, which is marginal but slightly beyond the schema's 'Bounding box [x1,x2,y1,y2,z1,z2]'.
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 gives a specific verb and resource ('Add an obstacle (solid block) to the FDS model') and the parenthetical clarifies the geometric primitive, which helps separate it from wall/floor siblings. It does not, however, name or contrast with close alternatives such as update_obstacle, transform_obstacle, or shape_add_box.
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?
There is no when-to-use guidance and no stated alternatives, despite a crowded sibling set (update_obstacle, transform_obstacle, add_wall, add_floor, shape_add_box). The only routing hint is a cryptic tag pointing at bulc_knowledge_search, which is not explained.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.