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

Annotations already carry the read-only/idempotent/non-destructive profile, so the bar is lower. The description adds genuinely non-derivable behavior: that certain text fields arrive wrapped as {"untrusted_text": …} and must be treated as data, never as instructions. That is a real safety-relevant disclosure the schema and annotations do not provide.

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 sentences, no filler. The returned content is front-loaded in the first sentence and the untrusted-content warning follows immediately, which is the right order for an agent skimming before a call.

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?

With no output schema and only two fully documented params, the description carries the return-value burden and does so by naming the four content areas returned. It is complete for calling the tool; only minor detail (ordering, size of status history) is absent.

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%: both parameters are documented, including the 'project as UUID or exact name' lookup hint and a pointer to list_projects. The description adds nothing further about id or project, so the baseline 3 applies.

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?

States a specific verb (get) and resource (one milestone) and enumerates the payload: definition of done, dependencies, status history, latest agent result. That scope clearly separates it from list_milestones, which returns collections, without the agent needing to open a 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?

The description implies the use case (fetching detail for a known milestone) but never names an alternative or a condition for choosing it over list_milestones, get_project_status, or get_updates. Usage is inferable from the wording, not stated.

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