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

Annotations already declare readOnlyHint=true, so the safety profile is covered. Beyond that the description adds only the underlying REST endpoint, which is not meaningful behavioral context for an agent; it says nothing about behavior when the id is absent, error handling, or returned data.

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 short sentences with no filler, and the core action is front-loaded. The trailing endpoint reference is slightly redundant but harmless retrieval context.

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 single-record read with annotations covering the read-only nature, the definition is minimally sufficient. With no output schema, it could usefully indicate what the returned opportunity contains or how missing ids are handled, so it is adequate rather than 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 description coverage is 100% for the single required opportunity_id, so the schema already carries the parameter documentation. The description adds no format, source, or constraint detail beyond restating 'by id', which is the baseline case.

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 ('Get') and resource ('a single opportunity by id'), which cleanly distinguishes it from the sibling list tools such as keap_list_opportunities. It is clear but never names or contrasts with a sibling, so it stops short of a 5.

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?

There is no explicit when-to-use guidance, no prerequisites, and no mention of alternatives. The only usage signal is inferred from the name/verb, which is insufficient for a 5-point score.

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