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Glama

storage_set

Destructive

Store a value in browser storage (localStorage or sessionStorage) and verify it by reading it back. Handles JSON encoding for non-string values.

Instructions

Write one key into localStorage or sessionStorage and read it back to confirm. area='local' (default) or 'session'. Values are strings; non-string values are JSON-encoded first.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
keyYes
areaNolocal
valueYes
timeoutNo
session_idNo

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault

No arguments

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

A4.1/5.0
Behavior4/5

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

Annotations already mark destructiveHint=true and idempotentHint=false; the description aligns by describing a write/overwrite operation. It adds useful context beyond annotations by disclosing the read-back confirmation and the JSON-encoding behavior for values. No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tight sentences place the core action first and add only essential detail. Every phrase contributes meaning, and there is no filler or repetition of schema/annotation content.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Core usage is covered well: write, storage area, value handling, and confirmation. However, with five parameters and no schema descriptions, the omission of timeout and session_id semantics leaves an agent guessing for advanced calls. The output schema helps, but the description alone is only minimally complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

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. It explains area values/default and value coercion, but does not explain key, timeout, or session_id. The claim that non-string values are JSON-encoded also sits awkwardly with the schema requiring value as a string.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific action ('Write one key'), the target resource ('localStorage or sessionStorage'), and an explicit confirmation step. It is immediately distinguishable from the reading sibling storage_get and makes the tool's purpose unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives clear context for when to use the tool: when persisting a single key to browser storage, with area selection and defaults explained. It does not explicitly name storage_get as the alternative or state conditions for avoiding this tool, but the write-focused framing makes the intended use clear.

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