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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the safety profile is covered structurally. The description adds only the vague claim 'privacy-filtered project metadata,' which does not explain what is filtered, what the write actually changes, or whether version conflicts (expectedVersion) are surfaced. It does not contradict the annotations, but it contributes little beyond them.

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?

A single short sentence with no padding and the core verb front-loaded. It is efficient, though the brevity here stems from under-specification rather than tight writing.

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 versioned mutation with 7 parameters (4 required), a nested object, an idempotency key, and optimistic concurrency via expectedVersion, yet the description explains none of this. With no output schema, an agent also gets no sense of what a successful start returns or what a version conflict looks like, leaving the definition inadequate for the tool's complexity.

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%, so the parameters are fully documented in the schema, making 3 the baseline. The description's mention of 'project metadata' loosely maps to the nested `details` object (summary/status/referenceIds) but adds no format, constraint, or usage detail beyond what the schema already states.

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 largely restates the tool name: 'inbox_start' becomes 'Update hosted inbox start,' and it is unclear whether this starts, resumes, or mutates an inbox record. The phrase 'privacy-filtered project metadata' gestures at a domain but does not explain the operation. No differentiation from siblings like inbox_claim, inbox_list, or complete_inbox_task.

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 when-to-use guidance, no prerequisites, and no named alternative. An agent cannot tell from the text whether this belongs before inbox_claim or after complete_inbox_task, or what state the inbox must be in.

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