Store user facts about themselves, recording replacements like a new city or job as updates while preserving older facts as history.
Store what the user said about themselves. Facts that replace older ones (a new city, a new job) are recorded as updates and the old fact is kept as history.
| Name | Required | Description | Default |
|---|---|---|---|
| text | Yes | ||
| user_id | No | default |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, and it does disclose a genuinely non-obvious behavior: superseded facts (new city, new job) are recorded as updates and the old value is retained as history, so nothing is destructively overwritten. It omits other behavioral context such as per-user scoping or duplicate handling, but the key mutation semantics are covered.
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 sentences, zero waste, with the core action front-loaded and the update/history caveat following immediately. Nothing is repeated from the name or title.
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?
An output schema exists, so return values need no explanation, and the tool is a simple two-parameter write. However, the unexplained user_id scoping and the absence of any routing guidance against forget/recall leave gaps for an agent operating in a memory-tool cluster.
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%, so the description must compensate and largely doesn't. It never explains what 'text' should contain (a sentence? a fact tuple?) nor what 'user_id' scopes, even though its 'default' value implies multi-user partitioning that an agent could easily get wrong.
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 (store) and a specific resource (facts the user shares about themselves), which clearly separates it from retrieval siblings like recall and list_memories. It stops short of naming any sibling explicitly, so differentiation is inferred from the verb rather than stated.
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?
Usage is only implied: an agent can infer it should call this when the user reveals personal facts, but there is no explicit 'use when' framing, no guidance on when to prefer forget or recall, and no mention of how this interacts with list_entities/list_memories.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.