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

Annotations already declare readOnly=false, destructive=false, idempotent=false and openWorld=false, so the safety profile is covered. The description adds meaningful context about lead-linking caution and non-creation of outreach leads, but says nothing about required permissions, duplicate handling, or what happens when a lead_id is invalid.

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 short sentences, front-loaded with the action, then the link constraint, then the exclusion. No filler, though the middle sentence is a caution rather than definitional content.

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?

This is a mutating tool with seven params at 14% schema coverage and no output schema. The description never explains the identity/relationship among id, company_id and lead_id, nor what the call returns (e.g., the created contact), leaving significant gaps an agent must guess at.

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 14% — only workspaceId is documented in the schema, and the description never explains id vs company_id, name, email, role, or the format/constraints of lead_id. With six required parameters largely undocumented, the description does not compensate for the coverage gap; 'optionally linked to an existing lead' is the only hint about lead_id.

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 ('Add a company contact') and scopes it with 'optionally linked to an existing PumpGTM lead in this workspace.' It also distinguishes itself from a key sibling by declaring 'Does not create or enroll outreach leads,' which separates it from add_leads/add_to_sequence without requiring the schema.

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 gives an explicit guardrail ('Never guess a lead match from a company name') and a clear exclusion ('Does not create or enroll outreach leads'), which tells the agent when not to use it. It stops short of naming the alternative tool to use for lead creation/enrollment, leaving that inference to the agent.

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