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

With annotations covering only read-only/destructive/idempotency flags, the description adds the substantive behavior: optimistic-concurrency semantics via expected_revision, the meaning of the lifecycle field ('your team's assessment; active never means Stripe-verified'), and explicit side-effect exclusions (does not send, enroll, or bill anyone). This is exactly the context an agent cannot get from the annotations.

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?

Four dense sentences, front-loaded with purpose, then the create/edit rule, then semantics warnings, then side-effect boundaries. No filler; the two lifecycle/status sentences overlap slightly but each adds a distinct guardrail.

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 9-parameter mutation tool with no output schema and near-zero schema description coverage, the description covers the risky parts well (concurrency, side effects, lifecycle interpretation) but leaves the agent guessing on several required fields (owner, domain, next_review_on) and on what happens when a stale revision is supplied.

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 11% (only workspaceId documented), so the description must compensate. It does explain expected_revision's dual create/edit role and clarifies lifecycle's semantics, but name, domain, owner, owner, next_review_on and success_plan format expectations remain undocumented in both schema and description.

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?

Specific verb+resource (create or revise a CRM company and its customer success plan), clearly distinguishable from siblings like get_company, add_company_contact and save_opportunity. The description also delimits scope by stating what it does not do (send, enroll, bill).

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?

Gives an explicit rule for create vs edit (new UUID plus expected_revision=0 for creation, current revision for edits) and a constraint on what may be entered ('Do not invent customer status'). It does not name alternative tools for adjacent tasks, so it stops short of a 5.

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