chrome_read

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

With no annotations, the description carries the full burden and does so well: it discloses that output is bounded, that sensitive fields and invalid/presentation ARIA nodes are filtered, that the snapshotId is ephemeral, and that exact nodeIds are returned for use by mutations. It omits auth/permission requirements and any rate or freshness caveats, keeping it short of a 5.

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 front-loaded sentences that move cleanly from what it reads, to exclusions, to return value plus usage. Tight and well-ordered, with only mild redundancy in the closing screenshot/coordinates disclaimer.

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?

No output schema exists, but the description compensates by naming the returned values (ephemeral snapshotId and nodeIds) and the filtering behavior. Combined with 100% schema coverage on both parameters, an agent has nearly everything needed, though permission/error behavior remains unstated.

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 description coverage is 100%, so max_chars and max_nodes (including defaults and hard caps) are already fully documented in the schema. The description only echoes the notion of boundedness without adding syntax or interaction detail, so the 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 (Read) and resource (bounded semantic DOM snapshot from the exact paired Chrome document), and the 'No screenshot or coordinates are used' clause distinguishes it from screenshot/ocr/click_mark siblings. An agent can tell it apart from ax_read and the visual tools without opening either schema.

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 an explicit when-to-use directive: 'run this immediately before every Chrome mutation', which is strong operational guidance. It does not, however, name sibling alternatives or state exclusion conditions (e.g. when to prefer ax_read or chrome_status), so it stops short of a full when/when-not treatment.

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