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

Annotations already declare this is a non-read-only, non-idempotent, open-world, non-destructive operation. The description adds a meaningful behavioral detail beyond annotations: the two-step preview-by-omitting-confirm pattern, which is essential for safe invocation.

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?

Three tightly written sentences with the core purpose front-loaded, followed by prerequisite sourcing and a preview instruction. No filler or repetition.

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?

The description covers the purpose, key ID prerequisites, and preview behavior, which is helpful. However, with only 38% schema coverage and no output schema, it should explain the required location_id and other undocumented parameters more fully for an 8-parameter mutation tool.

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 38%, so the description must compensate for many undocumented parameters. It covers sources for pipeline_id, pipeline_stage_id, and contact_id, but omits required location_id as well as name, status, monetary_value, and confirm semantics beyond the preview hint.

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 states a specific verb and resource: 'Create an opportunity' and clarifies it as 'a potential job' in a pipeline attached to an existing contact. This distinguishes it clearly from sibling update/list tools and gives an agent enough to select it correctly.

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 provides clear prerequisite guidance by naming highlevel_pipelines, highlevel_find_contact, and highlevel_create_prospect as sources for required IDs. It also gives an important usage instruction to call without confirm first to preview, though it does not explicitly state when not to use this tool.

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