update_profile_banner

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

With no annotations, the description fully discloses behavioral traits: it is destructive (⚠️), immediately replaces the banner, and provides size/format limits. This gives the agent a clear understanding of side effects.

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 extremely concise, using two short sentences plus a warning emoji. Critical information (destructiveness, replacement, constraints) is front-loaded, with no superfluous content.

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?

Given the presence of an output schema (not shown but indicated), the description need not explain return values. It covers purpose, parameter constraints, and behavioral effects comprehensively, making it sufficient for correct tool 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?

The schema covers the single parameter 'file_path' with a description. The tool description adds valuable constraints beyond the schema: 'Recommended size: 1500x500px. Supported: jpg, png, gif (max 5MB).' This fully informs the agent about image requirements.

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 clearly states the verb 'Change' and the resource 'profile banner/header image.' It distinguishes from sibling tools like 'update_profile_image' (avatar) and 'delete_profile_banner' by naming the specific resource.

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 includes crucial usage guidance: 'WARNING: This immediately replaces your current banner.' It also provides recommended size and supported formats, helping the agent understand constraints. However, it does not explicitly state when to use this tool over alternatives (e.g., for banner vs. avatar), though context from siblings makes it clear.

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