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

Annotations already cover idempotency (idempotentHint=true) and non-destructiveness (destructiveHint=false), so the bar is lower. The description adds that repeated calls are expected ('again after each meaningful chunk') and reinforces session-id reuse, which aligns with the session_id schema note about updating one row. It does not describe any additional side effects such as overwriting or storage behavior beyond what annotations and schema state.

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?

Two short sentences, no filler, and the most important timing rule is front-loaded. However, the description is so terse that some purpose information is missing, which slightly lowers it from a perfect score.

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?

With 16 parameters and several sibling tools that likely handle saving/context, the description is too sparse to let an agent confidently choose this tool. It doesn't explain what a checkpoint is, how it relates to palim_save_session/palim_save_context, or what the output schema returns. The rich input schema compensates for parameters but not for the missing high-level semantics.

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 the baseline is 3. The description adds no parameter-level detail beyond the schema; the only specific hint, reusing claude-code-<client session id>, mirrors the session_id property description already present in the schema.

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 tells the agent when to call the tool ('after connecting AND again after each meaningful chunk of work') but never states what the tool does — e.g., that it saves or updates a checkpoint. 'Checkpoint' in the name and the schema imply persistence, but the description itself lacks an explicit verb+resource statement. It does not distinguish itself from siblings like palim_save_session or palim_save_context.

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 precise timing guidance: call after connecting and after each meaningful chunk of work. It also provides a client-specific rule for Claude Code: reuse claude-code-<client session id>. It does not mention alternatives or exclusions, so it earns a 4 rather than a 5.

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