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

Annotations only declare the generic mutation profile (readOnly=false, destructive=false, idempotent=false, openWorld=false); the description adds the delivery mechanism (bell + notification center + agent inbox via list_messages), the hard 10000-character and text-only constraints, and an hourly send rate limit with batching advice. It also clarifies that the recipient reads it as a human message, which affects how content should be phrased — none of this is recoverable from 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?

Front-loaded with purpose and delivery outcome, then constraints, then optional param — a sensible order with no filler sentences. It is dense (a single long block covering five distinct topics) and the mixed Spanish/English against an English tool name is a minor friction, but nothing is redundant.

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 3-parameter, no-output-schema write tool this covers everything an agent needs: recipient resolution, content format limits, rate-limit behavior, workspace scoping, and how to retrieve the resulting message. No output schema exists, so the explicit pointer to list_messages/get_message adequately covers the return side.

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%, so the description carries the full burden and does: `to` accepts either a userId obtained from list_members or the email of a workspace MEMBER, `body` is markdown with auto-linked identifiers (DRAPPS-123) limited to text and 10000 chars, and `workspaceId` is optional with a documented default from the credential. Every parameter gains meaning absent from the bare string types.

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?

Opens with a specific verb+resource ('Envía un mensaje directo a otra persona del workspace') and immediately states where the recipient sees it, routing it clearly away from list_messages which it names as the read counterpart. An agent can distinguish this from add_comment and list_messages without opening any 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?

Gives concrete when-not rules: guests do not receive messages, you cannot write to yourself, and it explicitly is not a channel for commanding other agents. It names the helper tools for each sub-task (list_members for userIds, list_workspaces for workspaceId) and instructs batching due to the hourly cap.

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