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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the 'Read-only — it generates nothing and posts nothing' sentence largely restates structured data. It does add two pieces of genuine context: that nothing is written or posted as a side effect, and that the call is free (no quota cost). It says nothing about result shape, volume, or latency, so with annotations carrying the safety profile a 3 is right.

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?

Three short sentences, front-loaded with the outcome and followed by method and safety/cost caveats. The phrasing ('loudest silent ones', 'worth talking about') is colorful and slightly reduces precision, but nothing is padded or repeated.

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 two-parameter read tool with no output schema, the description covers what is counted, the time window, and the safety/cost profile, which is enough to call it correctly. The only gap is that it doesn't characterize the response beyond 'counts' and 'names', leaving the agent to discover the format.

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 coverage is 100%, with both parameters fully documented including fallback behavior on unresolved projects, so the schema does all the work. The description only alludes to a time window ('in a window') without adding format or bounds beyond what the schema already states. 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?

The description names a concrete resource ('what this project shipped that nobody outside it knows about') and concrete operations ('counts the milestones', 'names the loudest silent ones'), so an agent can tell this is a gap-analysis read rather than a listing or planning tool. It is vivid rather than precise about the unit of measure (milestones vs. updates), and it never contrasts itself with siblings like get_brief or list_drafts, so it stops short of 5.

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?

Usage is implied: ask for it when you want to know how much shipped work went unannounced in a time window. There is no explicit when-to-use vs. when-not, no named alternative for adjacent needs (e.g. reading drafts or briefs), and no stated prerequisites beyond the required project argument.

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