snapshot

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

With no annotations, the description carries the full behavioral burden. It usefully discloses the 90-second timeout and the ability to extend it with a caller-supplied budget, and implies a read-only snapshot behavior. However, it does not mention possible side effects such as the optional 'record' behavior, or describe the response format, which matters given the absence of an output schema.

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 three focused sentences: purpose, usage guidance, and a critical behavioral note. It is front-loaded with the main action, avoids fluff, and every sentence adds value.

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?

Given 24 parameters, no annotations, no output schema, and 52 sibling tools, this three-sentence description is insufficient. It does not explain the return structure beyond 'refs', does not cover side effects, and does not provide enough differentiation or parameter guidance for correct invocation in a complex MCP environment.

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 79%, slightly below the high threshold, so the description should add some parameter meaning. It adds context for timeoutMs by stating the default 90-second timeout and that a caller-supplied budget extends it, but it does not describe the five undocumented parameters or clarify the ambiguous 'diff option'.

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 identifies the action: 'Capture the accessibility tree or compare it with the previous session baseline' and mentions returning refs for semantic interactions. However, the phrase 'diff option' is ambiguous because no diff parameter exists in the input schema and a sibling tool named diff is available, so it does not fully distinguish this tool from related siblings.

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?

The description gives direct usage guidance: use the returned refs for subsequent semantic interactions and use the diff option to verify UI changes. This provides a clear context for when to invoke snapshot, though it does not explicitly state when not to use it or name alternatives beyond the vague 'diff option'.

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