validate_visuals

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

With no annotations, the description carries the full behavioral burden. It usefully discloses what the result contains (schema errors, unreadable spec literals, unsupported current-renderer specs) and what is silently skipped, but says nothing about permissions, whether it is purely read-only, or whether it fails fast versus collecting all errors.

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?

Three tight sentences with the scope constraint front-loaded and the exclusions last. No filler, though the GUID phrasing is more opaque than it needs to be for a reader without domain context.

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?

No output schema and no annotations, so the description must explain returns — which it partly does by enumerating the reported error categories. The gap is the sole input parameter and any indication of result shape or granularity (per-visual vs aggregate), which leaves it short of complete for a validation tool.

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 single parameter reportDir has no description in the schema. The description never mentions reportDir, its expected layout, or whether it points at a report root or a PBIR subfolder, so the agent gets no help on the one input it must supply.

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 (validate) and a narrowly scoped resource (PBIR visual containers whose visualType is the stable Vilsem Renderer GUID), which lets an agent distinguish this from a general validation tool. The term 'Vilsem Renderer GUID' is domain jargon not resolvable from the definition itself, so the boundary is clear in shape but not fully in content.

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 states a negative scope ('Native visuals and all report-level objects are neither validated nor reported'), which is genuine when-not guidance. However, it never names the alternative for those excluded cases (e.g. validate_spec, which exists as a sibling), leaving the agent to infer the routing.

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