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

No annotations are provided, so the description carries the full burden of behavioral disclosure, and it discloses almost nothing. It does not say whether the link is idempotent, what happens if the message is already linked to another client, whether it requires write permissions, or whether the operation is reversible.

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?

One short sentence with zero padding and the core operation front-loaded, so it is not verbose. However, its brevity is under-specification rather than efficiency, since the tool is a mutation with unaddressed behavioral and parameter questions.

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?

An output schema exists, so return values need not be described, but for a mutation with no annotations and 0% schema coverage the description is far too thin. An agent cannot tell from this text what preconditions hold, what side effects occur, or how to populate firm_id.

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 0% across three parameters. The phrase 'email message' and 'EAM client record' loosely maps onto message_id and client_id, but the third parameter, firm_id, is never explained, nor is the expected ID format or whether firm_id defaults to the caller's firm when empty.

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 (link) and both resources (an email message and an EAM client record), which is far more informative than the bare tool name. It stops short of a 5 because it does not distinguish this tool from siblings like assign_team_member or create_eam_client, which also attach entities to records.

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 guidance on when to use this tool, what prerequisite state must exist (e.g., the email and client must already be known to EAM), or what the alternative is if the email is not yet imported. The sentence merely restates the operation, leaving all routing decisions to inference.

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