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

Annotations already establish this is a non-read-only, non-destructive, closed-world mutation. The description adds meaningful behavior beyond that: the deal always starts in the FIRST stage, the starting stage cannot be chosen, and the result reports the actual pipeline_id. It does not cover permissions or error cases, but adds substantial operational context.

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 front-loaded with the core action and optional linkage, then layers in pipeline behavior. It is dense but each clause supports correct invocation. The parenthetical about website forms is slightly extraneous but serves to delimit scope, so the length is justified overall.

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 four-parameter mutation tool with no output schema, the description covers the critical behavioral quirks: default pipeline, immutability of starting stage, and the result's pipeline_id report. It omits error handling and permission requirements, but for this tool's complexity the description is nearly complete.

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 the schema already documents all four parameters. The description still adds semantic depth for pipeline_id—explaining its default behavior, its exclusivity within this toolset, and how to obtain valid IDs via list_pipeline_stages—which goes beyond the schema snippet.

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 first sentence states a specific verb and resource ('Create a deal') and immediately notes the optional contact linkage. It clearly distinguishes the tool from siblings like create_pipeline and move_deal_stage by explaining its role in the pipeline lifecycle.

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 explicitly says when to use pipeline_id versus relying on the default, names the alternative (move_deal_stage) for advancing stages, and directs the agent to list_pipeline_stages for IDs. It also clarifies that a pipeline created by create_pipeline stays empty until this tool is used with its ID.

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