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

Annotations already declare destructiveHint=true and idempotentHint=true, so the description's job is to explain *what* gets destroyed. It does that well: it warns that new content on a dynamic code silently redirects every already-printed copy — a consequence an agent could not derive from the schema. It does not cover permissions or what the response looks like, which keeps it below a 5.

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 sentences, zero filler, with the mutation scope front-loaded and the high-stakes consequence immediately after. Nothing needs to be trimmed and nothing important is buried.

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 tool with a very large nested schema and no output schema, the description leaves real gaps: it does not say whether the update is partial or full-replacement for design/content, nor that hosted content kinds (bio, pdf, app, business) are dynamic-only even though the schema hints at it. The dynamic-redirect warning is the one piece of behavior it properly carries.

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 only 25%, but the nested $defs carry extensive inline documentation (defaults, clamping, dynamic-only content kinds, upload restrictions), so the schema compensates for much of the gap. The description adds little beyond restating the three optional parameter groups and never clarifies whether supplying 'design' merges with or replaces the stored design.

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 ('Change') and resource ('QR code') and enumerates the mutable facets: name, content, design. An agent can separate it from create_qr_code/delete_qr_code/get_qr_code without any schema inspection. It stops short of a 5 because it never names a sibling or scope boundary explicitly.

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?

Usage is implied rather than stated: this is the tool for modifying a code that already exists, and the qrId parameter says it comes from list_qr_codes or create_qr_code. The second sentence gives a real caution about changing content on a dynamic code, but there is no explicit when-not guidance and no alternatives named for restoring or reverting.

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