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

With readOnlyHint=true and openWorldHint=false already declared, the description still adds real context: the whole project is compressed into the URL and 'nothing is uploaded' or requires an account, which materially explains the no-network behavior. It does not cover link size limits, expiry, or revocation.

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 return value and then the mechanism. Each sentence carries information, though the final sentence about opening the link in a browser overlaps slightly with the first.

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 zero-parameter, read-only tool with no output schema, the description covers everything an agent needs: what comes back (a URL), what that URL contains (the compressed project), and what a recipient can do with it (view the diagram and run the simulation).

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 zero parameters, so the schema-baseline of 4 applies. There are no arguments whose meaning the description would need to clarify, and the description correctly implies the link is derived from the current canvas state rather than from user input.

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 and resource: 'Returns a link that opens the current diagram on the BlockWerk canvas.' The mechanism (project compressed inside the URL, no upload) implicitly separates it from a file-oriented export, but no sibling such as export_diagram is named or contrasted explicitly.

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 only implied: the description explains what a recipient sees ('shows the diagram, where the simulation can be run'), which hints at a sharing scenario. It never states when to call this instead of alternatives like export_diagram, nor any prerequisites or exclusions.

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