memory_update_last

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

With no annotations provided, the description carries full behavioral burden. It says the tool updates the canonical checkpoint 'so future sessions know where work was left off', which conveys the main effect, but it does not disclose whether the previous checkpoint is overwritten, whether a missing checkpoint is created, or any other side effects.

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 key directive is front-loaded and every parameter is explained without filler. The block is reasonably compact for the amount of guidance it provides, though the 'AGENT DIRECTIVE' framing adds a small amount of stylistic overhead.

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 tool with 4 parameters, an output schema, and no enums or nested objects, the description covers when to call the tool, what it accomplishes, and what each parameter means. It does not explain overwrite behavior or routing to siblings, but an agent has enough to select and invoke the tool correctly in the intended checkpointing workflow.

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 0%, but the description compensates by explaining each parameter: content is a progress note or dictionary, project_root is a required absolute path, namespace has a default, and summary is an optional one-sentence description. Some semantics still remain abstract, such as what 'logical namespace' affects, so it is not a perfect 5.

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 explicitly names a specific verb and target: 'update the canonical project checkpoint ('system/last_memory')'. It also frames the tool as milestone/session checkpointing, which differentiates it from sibling tools like memory_store or memory_get_last by focusing on updating the single canonical 'last_memory' record.

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?

It gives explicit when-to-use conditions: 'whenever completing a milestone, making key project changes, or pausing work'. However, it does not state when not to use it or explicitly compare it with alternatives such as memory_store for new memories.

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