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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent write. The description adds genuinely useful context that MCP approval requirements are org-configurable and that business workflow approvals always apply, which affects whether the call completes immediately. It omits what gets created on failure or whether approval blocks the response.

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?

Two short sentences, front-loaded with the action, so it is not bloated. But the "same business service as the screen" clause is filler that consumes space without informing the agent.

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 mutation over a nested payload with zero parameter documentation, the description should at minimum clarify the required title and the site/phase scoping. An output schema exists, so return values need not be explained, but the input side is left almost entirely to the schema's field names.

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% and the single parameter is a nested object with eight meaningful sub-fields (title, siteId, phaseId, targetDate, status, completedDate, order, description). The description explains none of them — notably that title is required and that site/phase anchoring matters. With zero schema documentation, this is a significant gap.

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 ("Create milestone"), so the basic action is unambiguous. However, "using the same business service as the screen" is opaque internal jargon that does not help an agent distinguish this from siblings like update_milestone, create_milestone_column, or update_site_milestone_status.

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 notes that approvals apply, but gives no guidance on when to use this tool versus update_milestone or create_milestone_column, nor any prerequisites about needing a valid site or phase. Approval context is a behavioral note, not usage routing.

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