nexo_checkpoint_save

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

With no annotations provided, the description must carry the full burden. It clearly states the tool saves a checkpoint, is to be called before compaction, and that the checkpoint is re-injected as a Core Memory Block by a hook. This discloses key behavioral traits. It does not discuss destructive potential or auth needs, but for a save operation, these are less critical.

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 two sentences, front-loaded with the main action, and every sentence adds value. No redundant or extraneous information. It is optimally concise.

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 the moderate complexity (9 parameters, all simple strings, no output schema, no annotations), the description provides the core purpose and usage context. It explains what happens after saving (re-injected as Core Memory Block), which compensates for the lack of output schema. It does not explain return values, but for a save tool, this is sufficient.

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?

The input schema has 100% description coverage, so the schema already documents each parameter. The description does not add additional meaning for individual parameters beyond the overall usage context. According to guidelines, when schema coverage is high, baseline is 3. The description provides no per-parameter enhancement.

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 states the verb 'Save' and the resource 'session checkpoint for auto-compaction continuity'. It distinguishes from sibling tools like nexo_checkpoint_read (reading) and various nexo_continuity_* tools, as it specifically addresses checkpoint saving for compaction continuity.

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 explicitly says 'Call this BEFORE context compaction to preserve session state' and explains the subsequent behavior via PostCompact hook. This gives clear context for when to use the tool. However, it does not mention when not to use it or list alternative tools for similar purposes.

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