spatial_validate_placement

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

With no annotations provided, the description carries the behavioral burden. It explicitly states 'read-only' and says the tool 'reports' rather than modifies, which is a clear safety disclosure. It also reveals trace-dependent behavior by mentioning 'missing a trace hit' and lists the concrete diagnostic categories.

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 compact and well-structured: a clear purpose line, a KB pointer, a behavioral summary, and a relevant example. It is front-loaded with the most important information and contains no filler.

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 15 mostly undocumented optional parameters and no annotations, and the description explains only two of them via example. It gives strong high-level context and the output schema covers return values, but an agent still lacks enough guidance on how to target actors, configure traces, or interpret parameters like clearance_padding and include_evidence_handoff.

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 for 15 parameters. It only illustrates tag_filter and surface_tolerance via the example; the remaining parameters—query, actors, center, radius, trace_up, trace_down, ignore_self, class_filter, trace_channel, include_hidden, clearance_padding, include_evidence_handoff—are left to be inferred from their names and defaults. That is insufficient compensation.

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 leads with a specific verb and resource: 'Validate placed actors against nearby surfaces and bounds overlap.' It further enumerates the exact diagnostic outcomes—on-surface, floating, below/intersecting, missing trace hit, overlapping—which clearly distinguishes it from sibling tools like spatial_query_actors or spatial_surface_probe.

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 'post-placement bridge' implies this should be used after actors have been placed, and the example shows a concrete invocation. However, it does not explicitly say when to prefer this tool over alternative spatial validation/query tools, nor does it describe 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.