human_event_ack

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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is substantially covered. The description adds a useful caveat that it does not resume input or prove model receipt, but it does not explain what destructive state change occurs, what permissions are required, or what a successful acknowledgement means beyond the annotation hints.

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 description is short and front-loads the action, with the caveat following immediately. It is not padded, though its terseness contributes to the gaps in parameter and usage detail; from a conciseness standpoint, it is efficient.

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 tool with four required parameters, 0% schema description coverage, no output schema, and destructive/idempotent annotations, the description is insufficient. It does not explain parameter sourcing, expected response behavior, or the consequences of acknowledgement, leaving the agent under-informed before 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 0%, so the description must carry parameter meaning. It references an 'event token', likely receipt_token, but provides no explanation for event_id, session_epoch, pause_generation, or the token's format and source. Three of four required parameters 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?

The description gives a verb and resource: 'Acknowledge ... receipt using the event token.' However, 'MCP caller receipt' is jargon-heavy and does not clearly explain what the tool actually acknowledges or how it differs from sibling event/resume tools. The caveat 'Never resumes input' provides partial differentiation, but the overall purpose remains vague to an agent.

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 explicit guidance on when to use this tool versus alternatives such as human_resume, human_events, or human_pause. The statement 'Never resumes input' is a negative clarification but not a usage guideline. The agent is left to infer the appropriate context for calling an event acknowledgement.

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