标记会话已读/未读

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

With readOnlyHint=false and openWorldHint=true already signaling a mutation, the description adds real value by disclosing that only the MCP-side cursor is modified and the browser's unread markers are untouched. It also explains the reversibility of unread=true, though it doesn't describe any response or side effects on the unread count itself.

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?

Front-loads the core action and packs the three behaviors into a tight single sentence plus a scope sentence. Nothing is wasted, though the run-on structure slightly reduces scannability.

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 two-optional-parameter mutation tool with no output schema and no nested objects, the description covers purpose, both modes, and scope boundaries. It is essentially complete, missing only return/confirmation behavior, which is minor here.

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 both parameters are already documented in the schema. The description restates the same semantics (session optional, unread default false) without adding format or edge-case detail beyond the schema, so baseline 3 applies.

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: it updates this MCP's read cursor, with clear per-session vs. bulk semantics. It also distinguishes itself by clarifying the scope ('only this MCP's cursor, not the browser's unread markers'), which separates it from sibling read/list tools.

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 describes the two operating modes: supply session to target one conversation, omit it to mark all unread at once, and unread=true to reverse/clear the cursor. It gives clear context for invocation but does not name alternative tools for related jobs.

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