Generate a QR code for a task list (event) that workers can scan to access tasks. TaScan draws the QR itself (an SVG, also returned as a data: URI in qr_image_url); no third-party QR service ever sees the link.
| Name | Required | Description | Default |
|---|---|---|---|
| style | No | Reserved for saved QR styles (SR-P4c): accepted and ignored today | |
| list_id | Yes | Task list (event) ID |
Changes observed during successful MCP inspections.
Input schema / properties / styleAdded value: +{
+ "description": "Reserved for saved QR styles (SR-P4c): accepted and ignored today",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already flag idempotent, non-destructive, closed-world behavior, and the description adds real value beyond them: the QR is drawn in-house, returned as an SVG and a data: URI in qr_image_url, and no third-party service sees the link (a privacy guarantee). It doesn't explain what the non-readOnlyHint generation persists, but the output-format and privacy disclosure is strong.
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 tight sentences: capability first, then a concrete behavioral detail, with zero waste. Everything is front-loaded and earns its place.
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 no output schema, the description usefully explains what is returned (SVG plus a data: URI), and annotations cover the safety profile while the schema covers both params. It could say a bit more about the non-read-only side effect, but nothing critical is missing for 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 coverage is 100%, so both parameters (list_id and the reserved/ignored style) are already documented in structured data. The description only implicitly maps to list_id via 'task list (event)' and adds no syntax or format detail beyond the schema, so baseline 3 applies.
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?
States a specific verb (Generate) plus resource (QR code) plus target (task list/event) and the outcome (workers scan to access tasks). No sibling tool deals with QR generation, so an agent can immediately tell this apart from the rest of the catalog.
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 conveys the scenario (giving workers scannable access to a task list), which implies when to use it, but it names no alternatives or exclusions and gives no preconditions such as requiring an existing list_id.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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