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

Beyond the annotations it discloses the permission requirement ('Needs the permission that edits a Jam's title'), the security-relevant side effect that the URL becomes visible on a possibly public share page, the credential-rejection rule, and the return value ('Returns the resource'). The idempotency statement merely restates idempotentHint, but the remaining context is substantive and consistent with readOnlyHint=false and destructiveHint=false.

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?

Purpose, label guidance, idempotency, visibility warning, and permissions arrive in a logical order with the core action front-loaded. It is slightly long, and the motivational 'record proof of your work' sentence overlaps with the opening examples, but no sentence is pure filler.

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 mutation tool with no output schema, the definition covers what is created, what is returned, permissions, idempotency, public-visibility risk, and input rejection rules. An agent has everything needed to decide to call it and to construct valid, safe arguments.

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%, so the baseline is 3, but the description adds real meaning: it explains when a `label` is needed and what happens without one (viewers see the host and path), and it constrains `url` beyond the schema by forbidding token-bearing or credentialed URLs. The meta-parameters intent and llm_model are left to their schema text.

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 opens with a specific verb and resource: 'Attach a URL to a Jam', and gives concrete examples of what a URL can be (pull request, CI run, another Jam). It does not differentiate itself from the inverse sibling removeResource or clarify its relationship to updateJam, so it stops short of the top mark.

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?

It provides a clear when-to-use rule ('When you record proof of your work, add the pull request or ticket it proves as a resource') and a strong when-not-to: do not pass URLs carrying tokens, and URLs with user/password are refused. It never names an alternative tool (e.g. removeResource for detaching), so there is no explicit alternative routing.

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