read_hiddenUnlock and read a hidden session's transcript without restoring it, then incorporate it into the current visible conversation.
Returns the transcript of a hidden local session without restoring it. Requires unlock. Note: the text becomes part of the current, visible conversation.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Vault id or original session id (prefix of 6+ chars works) | |
| max_chars | No |
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only declare readOnlyHint, so the description carries the rest and does so well: it discloses an auth prerequisite ('Requires unlock') and a non-obvious side effect ('the text becomes part of the current, visible conversation'), which is exactly the kind of privacy consequence structured fields will not convey. It does not merely restate readOnlyHint.
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?
Three short sentences, front-loaded with the action and its scope, then prerequisite, then the warning. No filler; every clause carries information.
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 2-param read tool with no output schema and only a readOnlyHint annotation, the description covers return content, prerequisite, and side effect. The only gap is the undocumented max_chars parameter, which leaves truncation behavior unclear.
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 50%: 'id' is documented in the schema (including the 6+ char prefix hint), but 'max_chars' has no description anywhere. The description adds no parameter-level meaning, so it fails to compensate for the undocumented truncation parameter.
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 and resource (returns the transcript of a hidden local session) plus the scope qualifier 'without restoring it', which directly distinguishes it from the sibling restore_hidden. An agent can tell what this does and what it does not do without opening the schema.
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?
'Without restoring it' implicitly routes the agent here when the session should stay hidden, in contrast to restore_hidden. The prerequisite 'Requires unlock' is stated, but the alternative (restore_hidden) is not named explicitly, so it stops just short of full when/when-not guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.