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

The description adds that it handles both URL forms and outputs a list of equation rows, which is useful. However, the output schema already specifies the return structure, and annotations declare read-only/ non-destructive. It doesn't cover edge cases like invalid URLs or decoding failure, but given the annotations cover safety, a 3 is appropriate.

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?

The description is a single sentence that is informative and front-loaded with the main action, then details the input forms and the purpose. No wasted words.

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?

The tool is simple (single parameter), has a clear output schema, and annotations cover the read-only nature. The description covers the input forms and purpose, which is everything an agent needs to call it correctly and understand the output.

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 schema fully documents the 'url' parameter as an equation.io graph URL, so coverage is 100%. The description adds value by specifying the accepted forms (#-fragment or /g/), which is beyond the schema, but it's a minor addition. Baseline 3 is appropriate.

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 clearly states what the tool does: decodes an equation.io link into a list of equation rows. It specifies both URL forms (#-fragment and /g/ share) and mentions the purpose (to edit and rebuild via encode_graph_url), which distinguishes it from its sibling.

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?

Explicitly states when to use this tool (when you need to edit the graph's rows) and names the alternative for the reverse operation (encode_graph_url). This is a clear usage guideline.

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