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

Annotations already flag destructiveHint=true and readOnlyHint=false, and the description is consistent with them (marking read clears bell notices). Beyond the annotations it adds the authorization constraint ("Only the project owner") and the exact scope of what is cleared, though it does not say what happens on repeat calls or whether an error is returned for non-owners.

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 compact clauses: the effect is front-loaded, then the parameter choice, then the permission gate. Every sentence carries load with no 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 no-output-schema mutation tool, the description covers effect, target scoping, parameter exclusivity, and authorization. The only gaps are return behavior and idempotency/failure cases, which are minor given both parameters are optional-by-construction and the side effect is disclosed.

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 the schema lacks: the mutual-exclusivity rule ("Give exactly one of the two") and the semantic contrast between cardId (one task) and boardId (every one of the project), which the terse schema descriptions ("The task." / "The project.") do not convey.

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 (marks as read) and a specific resource (the client's portal comments), plus the secondary effect of clearing the associated bell notices. An agent can distinguish this from generic notification tools because the scope is tied to client portal comments on a task or project.

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?

Gives explicit operating conditions: pass exactly one of cardId (one task) or boardId (every comment in the project), and requires the caller to be the project owner. It does not, however, differentiate from the neighboring mark_notifications_read tool, leaving that disambiguation to the agent.

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