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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral information beyond them: the host-dependent rendering (interactive widget vs. identical data as JSON), which matters for how the agent should consume the result. It stops short of describing size limits or whether the archive breakdown is always included.

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 clauses, both load-bearing: the first defines the view and its encodings, the second explains the host-dependent delivery. The purpose is front-loaded and there is no filler or repetition of the title.

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 parameters and no output schema, the description must convey what comes back, and it does describe the grouping, the lifecycle coloring and the whole-archive breakdown plus the JSON fallback. It could go one step further and sketch the JSON payload shape, but for a read-only display tool this is close to complete.

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?

The tool takes no parameters, so there is nothing for the description to disambiguate. Baseline for a zero-parameter tool applies; the description correctly signals that the output is fixed-shape rather than configurable.

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 specific verb ('Show') and a well-defined resource ('curated public projects on a timeline'), plus the exact visual encodings (grouped by last-active month, colored by lifecycle). It is clearly a distinct visualization of the archive rather than a plain listing, though it never names the near neighbours show_project_gallery or list_projects to sharpen the boundary.

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 'use this when... instead of X' guidance; the choice between this view and show_project_gallery or list_projects is left to inference. The one piece of selection context given is environmental – MCP Apps hosts get an interactive timeline, others get JSON – which helps an agent predict the result but not decide between tools.

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