Create Custom Web Tab

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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the agent knows this is a mutating, non-destructive operation. The description adds meaningful context by defining the artifact (URL-based tab that opens external/page content) and clarifying it is a creation action, complementing the annotations without contradicting them.

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: two purposeful sentences introducing the tool and distinguishing it, followed by a concise parameter list with inline examples. No filler. The parameter list is slightly redundant with the schema, but the overall structure is efficient and front-loaded with the core purpose.

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 simple creation tool with well-annotated schema, the description covers the core context: what it creates, when to use it, how it differs from siblings, and what each parameter means. It does not explain return values or permissions, but given the 5-param schema and no output schema, the description is sufficiently complete for an agent to invoke it correctly.

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 100%, so the schema already documents each parameter. The description's parameter list mostly repeats schema details, but it adds small clarifications like 'no spaces' for fullName and provides examples (e.g., 'https://example.com'). This slightly enhances but does not significantly exceed the schema's value, so baseline 3 is appropriate.

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 opens with 'Creates a Custom Web Tab (URL-based tab) that opens an external URL or web page within the Salesforce UI'—a clear verb+resource combination. It explicitly distinguishes itself from sf_create_tab, which 'creates object-based tabs,' making the unique purpose instantly apparent.

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 provides explicit usage guidance: 'Different from sf_create_tab which creates object-based tabs. Use when you need a navigation item that points to an external website, an internal Visualforce page by URL, or a custom web app.' This names the alternative and gives concrete use cases, fully satisfying the when-to-use vs alternatives requirement.

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