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

Annotations already declare the mutation/safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=false), and the description adds genuinely new behavior: the resulting state is "account created in not_started." It does not address duplicate handling despite idempotentHint=false, which is the one behavioral trait left undisclosed.

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 core action and the mandatory-field gate are front-loaded in the first two sentences, and the closing "Effects:" line is a compact, high-value signal. The parenthetical CRM-3 / CRM-12 references add slight noise for an agent that has no way to resolve them.

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?

With 9 parameters and no output schema, the description covers the mutation's landing state but says nothing about what is returned (e.g. the new account id) or how duplicates are handled given idempotentHint=false. Those are the remaining gaps an agent would hit on first invocation.

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% and each of the 9 fields carries a substantive description, so the schema does the heavy lifting. The description only reinforces that why_them and source_url are mandatory and frames why_them as an argument for the campaign goal — marginal added meaning over the schema's own text.

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?

"Add a researched account to the list" gives a specific verb (add) and resource (account) plus a scope qualifier (researched, curated list) that separates it from funnel-style capture tools. It stops short of naming a sibling (e.g. crm_add_contact vs crm_add_account), so the agent must infer from the tool names which one to pick.

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?

Provides an explicit admissibility test: why_them and source_url are mandatory, and "If you cannot say why them and what changed, it is not a target yet" is a real when-not-to-use rule. No alternative tools are named, so the agent gets a gate but not a routing decision.

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